JPS598738B2 - Santen Ondo Saseigiyoshikikunetsouchi - Google Patents

Description

Detailed Description of the Invention The present invention relates to a device that temporarily stores heat received in a heat exchanger in a heat storage tank and uses this heat for hot water supply, air conditioning, etc. The temperature at three points in the heat storage tank is detected, and the heat medium is circulated only when the temperature relationship between the stiffeners is constant to efficiently store heat in the heat storage tank.
This invention relates to a point temperature survey control type heat storage device.

2. Description of the Related Art A conventional heat storage device including a heat exchanger and a heat storage tank includes, for example, a solar water heating device.

This solar water heating system guides a heat medium heated by a heat exchanger to a heat storage tank, and uses the heat stored in the heat storage tank to heat the room.

However, in such solar water heating systems, on cloudy days or at night, the solar radiant energy decreases or almost disappears, so the temperature of the heat medium in the heat exchanger is lower than the temperature of the heat medium in the heat storage tank. Sometimes it happens.

In such a case, if the heat medium in the heat exchanger is directly fed into the heat storage tank, the temperature inside the heat storage tank will drop and the thermal efficiency of the device will decrease.

To solve this problem, conventionally, two spiral-shaped bimetal thermosensors connected by a spindle were placed inside the heat exchanger and the heat storage tank, and the rotation of the spindle was There is a so-called two-point temperature difference control type heat storage device in which the heat medium is circulated only when the heat medium temperature of the heat exchanger is higher than the heat medium temperature in the heat storage tank in conjunction with a pump motor.

However, inside the heat storage tank, the heat medium usually has a temperature distribution of high temperature at the top and low temperature at the bottom.

On the other hand, heat exchangers are usually formed into a fairly dog-shaped shape in order to increase heat exchange efficiency, and the heat medium inlet is connected to the bottom of the heat storage tank through a recovery pipe, and the heat exchanger is heated by solar heat. The temperature at the heat medium outlet is higher than that at the outlet of the medium, and the temperature distribution becomes uneven within the heat exchanger as well.

For this reason, the temperature is detected by one temperature sensing element placed at an appropriate location on each of the heat exchanger and the heat storage tank, and the detected temperature on the heat exchanger side is determined from the temperature on the heat storage tank side based only on the relationship between the temperatures at these two points. Even if it is detected that the temperature is higher than the detected temperature of If the pump is operated in such a case, the stable heat storage state will be disrupted, and the thermal efficiency of the device may be reduced and the pump may be turned off. If it is detected only at one point, it is not quantitatively clear whether or not the heat exchanger is in an effective heat collecting state.

For this reason, there was a problem in that if the circulation system was activated when the heat collection was not in an effective state, the thermal efficiency of the device would be reduced.

The present invention has been made in view of this point, and detects the temperatures at three points, the inlet and outlet of the heat medium in the heat exchanger and the inside of the heat storage tank, and detects the temperature at three points only when these temperatures have a preset temperature relationship. It is an object of the present invention to provide a three-point temperature difference control type heat storage device that can efficiently store heat in a heat storage tank by driving a pump and circulating a heat medium using a point temperature difference control device.

Embodiments in which the present invention is applied to a solar water heating system will be described in detail below with reference to the drawings.

In Fig. 1, 1 is a solar heat exchanger, and a delivery pipe A is provided from the heat medium outlet side 1' of the heat exchanger 1 to send out the heated heat medium toward the heat storage tank 2. has been done.

The heat storage tank 2 has a vertical shape so that the heat medium maintains a temperature distribution of high temperature at the top and low temperature at the bottom.

Further, a recovery pipe B is provided from the lower part of the heat storage tank 2 through a circulation pump P to send a low-temperature heat medium toward the heat medium inlet side 1'' of the heat exchanger 1.

Furthermore, the heat medium inlet side 1' and the outlet side 1' in the heat exchanger 1
For example, each temperature-sensitive resistor D1s is made of PT.
D2 is arranged.

On the other hand, the same <pt temperature-sensitive resistor D3 is also arranged in the heat storage tank 2.

And temperature-sensitive resistors D, , D arranged at these three points
2, D3 have the same resistance value at the same temperature, and are electrically led to the three-point temperature difference control device 3. 3 points O 1 temperature difference control device 3 is detected by each temperature-sensitive resistor. temperature T of the inlet side, outlet side and heat storage tank of the heat medium,
, T2, and T3 have a preset temperature relationship, the pump motor M is driven by the output via an appropriate switch, and the circulation pump P circulates the heat medium.

Pipes C and D installed at the upper and lower parts of the heat storage tank 2 are respectively used to guide the heat medium in the heat storage tank 2 into the room or to recover it for use in heating, etc. The three-point temperature difference control device 3 will be described below.

As shown in FIG. 2, a temperature-sensitive resistor D1 is led from the heat exchanger 1 and the heat storage tank 2 to the three-point temperature difference control device 3 through conductive wires.
, D2, and D3 are connected in series with fixed resistors R1, R2, and 4R3 to form the combinations of R1-D1, R2-D2, and R3-D3, respectively.

R1, R2, and R3 also have the same resistance value, and each series connection line of RI Di, R2 D2, and R3-D3 is connected in parallel to the power source EV.

Also, the intermediate connection point 5 between R1 and D1 is the first comparator C.
1, the intermediate connection point 6 between R2 and D2 is common to each terminal of the first and second comparators C, , C2 (7), and the intermediate connection point 7 between R3 and D3 is the 2 comparator C2's ←) terminals, respectively.

That is, the four resistance elements R1, R2, D1, and D2 form one Bridge circuit, and the four resistance elements R2, R3, D2, and D3 form another bridge circuit.

The first and second converters C1 and C2 compare the input voltage to the (G) terminal and the input voltage to the (F) terminal, and only when the input voltage to the (G) terminal is high, the input voltage to the (G) terminal is high. It outputs a high level, ie, f1'' to the output terminal.

Furthermore, these first and second comparators C1,
Each output terminal 8 and 9 of C2 are led to two input terminals of a canand circuit 10.

This ten-do circuit 10 outputs a ``0'' level voltage when a ``1'' level voltage is input to both of its two input terminals, and this ``θ'' level output closes the switching circuit S to drive the motor M to circulate the circuit. The temperature-sensitive resistor attached to the heat exchanger 1, etc. is not limited to a resistor with a positive temperature coefficient like PT, but also one with a negative temperature coefficient like a thermistor can be used. You can.

At this time, the first and second comparators "1 t C2
The polarity of (g), ←) of each input terminal of pt can be reversed from that when using pt. Also, NAND circuit 10 to which the output of converter 0 valetor C1+C2 is led
However, as long as the switching circuit is closed when the output is at the "1" level, it is no problem to replace it with an AND circuit.

In this way, each component of the three-point temperature difference control device 3 can be modified as appropriate.

Next, the operation of the three-point temperature difference control type heat storage device according to the embodiment of the present invention configured as described above will be explained.

Let us now assume that the temperatures of the heat medium inlet side 1'', outlet side 1', and heat storage tank 2 of the heat exchanger 1 are T1, T2, and T3, respectively.

At the beginning of the startup of the device or in a state where the heat exchanger 1 is receiving heat, the relationship T1<T2≧T3 holds.

Here, the detection temperature T3 on the heat storage tank 2 side is lower than or almost equal to the temperature T2 on the heat medium outlet side 1' of the heat exchanger 1 means that the temperature sensitive carrier D3 on the heat storage tank 2 side is This refers to the case where it is placed on the upper side.

In such a temperature state, as shown in FIG.
Since the PT temperature sensitive resistors D1, D2, and D3 have positive temperature coefficients, v2 and ■3 change as follows: ■1<v2>v3.

Such a change in potential is caused by each comparator C1,
A higher voltage is input to the (g) input terminal of C2 than the ←) input terminal.

Therefore, each comparator C1, C,,
“The output of the NAND circuit 10 is '0''.
level, the switching circuit is closed, the motor M is driven, and the pump P is operated.

As a result, the heat medium that is always heated to a higher temperature T2 than the temperature T3 of the heat storage tank is guided above the heat storage tank and is efficiently stored in the heat storage tank.

On the other hand, in the case of nighttime or cloudy weather, most of the solar radiant energy disappears or decreases, and the heating amount becomes small, so that the temperature T2 at the heat medium outlet of the heat exchanger becomes lower than that of the heat storage tank. When the temperature (temperature on the upper side of the heat storage tank) becomes lower than T3, that is, when the temperature relationship becomes T2<T3, V2<V3, and the second converter C2 receives a higher voltage (→ terminal side) than the terminal side. is input, its output becomes a 10" level voltage, and the NAND circuit 10 output also becomes a "1" level output, and the bomb P does not operate. This 0 relationship is the temperature of the heat exchanger 1 and the heat storage. The bomb does not operate not only in the temperature relationship with the tank 2, but also in the case where the heat medium inlet temperature T1 is higher than the outlet temperature T2 in the heat exchanger 1, that is, in the case where the temperature relationship is T1>T2. As shown in Fig. 2, the fixed resistor R1, which constitutes the bridge,
The values of R2 and R3 are set equal.

Therefore, in the relationship T1<T2>T3, if T2 is even slightly higher than T3, the pump will operate.

However, while maintaining the relationship between R2 and R3, only R3 is made a variable resistor, and in the bridge circuit of R2, R3, D2, and D3, the balance of potential is adjusted in advance so that the relationship of v3>v2 is established. If the temperature T2 at the heat medium outlet 1' of the heat exchanger 1 is higher than the temperature T3 of the heat storage tank 2 by more than a certain temperature difference, such as 5 degrees Celsius or more or 10 degrees Celsius or more, if it is turned in the opposite direction where it does not operate, It is also possible to circulate the heat medium by driving only the pump.

This can be similarly set for the relationship between T1 and T2.

As described above, according to the embodiment of the present invention, if the temperature T2 at the heat medium outlet of the heat receiver G is higher than the temperature T3 of the heat storage tank and the temperature T at the heat medium inlet of the heat receiver G is bluer, that is, T1<T.
2〉T3 or T1〈T2≧T3 Only when the pump is driven by the three-point temperature difference control device, only the high temperature heat medium flows into the heat storage tank 2, and heat is stored efficiently without any heat loss. It has the excellent effect of

In addition, in such a heat medium inflow state, the inside of the heat storage tank 2 is set to a temperature distribution state where the upper part is high temperature and the lower part is low temperature.

However, a high temperature heat medium is always supplied from the heat storage tank through the pipe C for purposes such as heating, making it an effective heat storage device.

In the above-described embodiments, the heat source of the heat exchanger is solar heat, but the present invention is not limited to solar heat as the heat source, but may also be an electrical conflict.

That is, the present invention can also be applied to devices that effectively use electric power at night to store heat in a heat storage tank and utilize the heat during the day, such as electric boilers and electric input heater devices.

As detailed above, according to the present invention, the temperature at three points in the inlet and outlet of the heat medium in the heat exchanger and in the heat storage tank is detected,
Inlet temperature T1 and outlet temperature T2 of the heat medium in the heat exchanger
, and the temperature relationship between the temperature inside the heat storage tank T3 is T,<T2″?
:． At T3, the pump is driven by the three-point temperature difference control device to circulate the heat medium, so the heat exchanger is in an effective heat collection state V- and the heat medium sent out from the heat exchanger is The heat medium can be circulated only when the temperature inside the heat storage tank is higher than or almost equal to the temperature inside the heat storage tank, so there is no heat loss and heat can be stored in the heat storage tank extremely efficiently. It is.

In addition, only temperature-sensitive resistors are installed in the heat exchanger and heat storage tank.
Since this is electrically guided to the three-point temperature difference control device, there is also the effect that there is no problem even if the heat exchanger and the heat storage tank are installed at a suitable distance.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing an example of a three-point temperature difference control device applied to the device shown in FIG. 1: Heat exchanger, 1', 1'': Outlet and inlet of heat medium, 2
: Heat storage tank, 3: Three-point temperature difference control device, 10: NAND circuit, M: Motor, P: Pump, A, B: Delivery and recovery pipes, D1, D2, D3: Temperature sensitive resistor, C1, C2: first and second comparators;

Claims (1)

[Claims] 1 A heat medium circulation pipe is provided between the heat exchanger and the heat storage tank via a pump, and temperature-sensitive resistors are arranged at three points at the inlet and outlet of the heat medium in the heat exchanger and in the heat storage tank. At the same time, each of these temperature-sensitive resistors is electrically guided to a three-point temperature difference control device, and the temperature relationship between the inlet temperature T1, outlet temperature T2, and temperature T3 of the heat medium in the heat exchanger is determined. A three-point temperature difference control type heat storage device, characterized in that when T1<T2≧T3, the pump is driven by the output signal of the three-point temperature difference control device to circulate the heat medium.