JPH1123079A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator to cope with a trouble, such as ozone fracture and warming of a globe by a method wherein a natural refrigerant is used in a circulation cycle on the secondary side, a booster is arranged in a position below primary and secondary heat-exchange parts, and a solenoid valve is arranged on the outlet side of a boosting device. SOLUTION: A secondary refrigerant, being a natural refrigerant such as CO2 , radiated and condensed by a refrigerator 1 on the primary side is fed to a heat- exchanger 2 on the secondary side, where by absorbing heat a substance to be cooled is cooled. A secondary refrigerant evaporated by the heat-exchanger 2 on the secondary side is returned to the refrigerator 1 on the primary side, and is caused to drop under own weight in a liquid reservoir 51 situated downstream from the condensing part of the refrigerator 1 on the primary side, and stored therein. A secondary refrigerant in the liquid reservoir 31 is supplied under own weight to a booster 53 through a check valve 52. When a liquid refrigerant is sufficiently stored in a booster 53, solenoid valves 54 and 56 are closed. A secondary refrigerant is heated by a heating device 57 to increase the internal pressure of the booster 53, and the secondary refrigerant is fed to a heat-exchanger 2 on the secondary through a piping 3 on the secondary side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration system using a natural refrigerant or a mechanical pump replacement engine (including temperature and humidity control, such as external cooling and heating of the original refrigeration, or air conditioning; the same applies hereinafter). .

[0002]

2. Description of the Related Art FIG.
Shows a conventional refrigeration system, and the system is composed of a primary side having a compression-type cycle installed outdoors and a secondary side for air-conditioning the room. At the time of cooling, on the primary side, the primary refrigerant compressed by the compressor 11 is switched by the four-way valve 12 to condense and liquefy the refrigerant in the heat source side heat exchanger 13 having the fan 14, and then decompressed by the expansion valve 15. Is evaporated in the primary / secondary heat exchanger 16 and the four-way valve 12 and the accumulator 1
, And is sucked into the compressor 11. On the other hand, on the secondary side, the secondary refrigerant pumped by the pump 18 is the primary / secondary heat deviser 1
At 6, the room is cooled by the refrigerant on the primary side and the room is cooled by the indoor heat exchanger 19 having the fan 20, and then returns to the pump 18. During heating, the flow path is switched in the opposite direction by the four-way valve 12 so that the primary
The secondary refrigerant heated by the secondary heat exchanger 16 circulates through the indoor heat exchanger 19 to heat the room. In the case described above, a Freon-based refrigerant R22 or the like is used as a primary refrigerant, and water is used as a secondary refrigerant.
In many cases, brine or the like is used.

However, some of the CFC-based refrigerants on the primary side cause problems from the viewpoint of ecosystems or global warming due to the destruction of the ozone layer. In the case of circulation, there is a problem that the room may be flooded due to leakage.

[0004] In order to cope with the above-mentioned problem of chlorofluorocarbons on the primary side, there is an example in which ammonia as a natural refrigerant is used. However, this ammonia has problems of toxicity, explosiveness, and corrosiveness to copper. , Use conditions are extremely limited,
I don't want to use it much. Recently, Internat
ional Status Report on Compression Systems with Na
tional Working Fluids (1996/2, Report No HPP-AIV22
-2) shows the operation of the ammonia system using CO ₂ as the secondary refrigerant for several months.
Since O ₂ is circulated by a pump, there remains a problem in reliability and high cost generally caused by high pressure. Although an example of an NH ₃ / CO ₂ system is also shown, it is a natural circulation system using gravity, and there is no freedom in flow rate control. When a natural refrigerant is used in this way, problems arise in terms of toxicity, reliability, cost, and flow rate control.

When attention is paid to the pump from a completely different viewpoint, there is a prior art disclosed in Japanese Utility Model Laid-Open No. 6-40771. FIG. 16 shows a refrigerant forced circulation device according to the prior art, in which the refrigerant is forcedly circulated without using a mechanical pump when sending the refrigerant to a place where natural circulation is not possible or a distant place. That is, the secondary pipe 3 of the primary refrigerator 1 is passed through the secondary heat exchanger 2 that cools the object to be cooled, and a transport unit that further transports the secondary refrigerant in the secondary pipe 3. In this case, not only the cooling of the object to be cooled but also forced circulation is performed.

The transfer means is not a mechanical pump which requires power and lowers the overall efficiency and has a problem in durability. Instead, the backflow prevention means 4a and 4b are located at a low position in the downstream pipe 3 of the primary refrigerator 1. , A refrigerant storage container 5, a heater 6, and the like, and the liquid refrigerant from the refrigerator 1 is supplied to the refrigerant storage container 5.
When the pressure inside the container 5 rises above the pressure applied to the backflow prevention means 4a, the refrigerant is extruded from the backflow prevention means 4a toward the secondary heat exchanger 2. When the pressure in the refrigerant storage container 5 is reduced by turning off the heater 6, the refrigerant is intermittently circulated by repeating a cycle in which the refrigerant from the refrigerator 1 flows again. In FIG. 16, 7 is a pressure detector, 8 is a control means, and 9 is an on / off switching means of the heater 6.

[0007] The transport means is a pump 1 shown in FIG.
8 and the like, and is effective for circulating the refrigerant at a high place or at a distance.

However, after the pressure inside the storage container 5 is increased and the refrigerant is forced to circulate, the refrigerant temperature inside the storage container 5 heated by the heater 6 decreases in order to introduce the refrigerant into the storage container 5 again. Therefore, there is a problem that the response becomes slow and heat loss occurs when the heat capacity of the liquid refrigerant is considered.

In view of the above problems, the present invention drives a natural refrigerant having a zero ozone depletion potential and an extremely low global warming potential without using a chlorofluorocarbon-based refrigerant, and is free from leakage without using water or brine. It is an object of the present invention to provide a refrigeration apparatus that eliminates problems such as being flushed. Furthermore, the present invention provides a refrigerating apparatus which uses other natural refrigerants without using ammonia which is a problem due to toxicity and the like, and which has a slow response and reduces the occurrence of heat loss in a transport means which replaces a mechanical pump. With the goal.

[0010]

The present invention that achieves the above object has the following matters specifying the invention. (1) In the secondary circulation cycle, using a natural refrigerant, a booster is provided via a check valve that forms a flow path in only one direction at a position below the primary and secondary heat exchange units, An electromagnetic valve for controlling the opening and closing of the flow path of the natural refrigerant is provided on the outlet side of the pressure increasing device. (2) In the above (1), a liquid reservoir is provided between the primary / secondary heat exchange section and the check valve. (3) In the above (1) and (2), in the secondary side circulation cycle, the flow path is opened / closed in parallel with the check valve between the primary / secondary heat exchange section and the booster. A pressure equalizing pipe provided with an electromagnetic valve to be controlled is provided. (4) In the above (3), two sets of a pressure equalizer having an electromagnetic valve in parallel with the check valve on the inlet side and a booster having an electromagnetic valve on the outlet side are provided in two sets. And (5) In the above (4), the solenoid valve of one pressure equalizing pipe is closed, the heating device provided in the booster is turned on, the solenoid valve at the pressure booster outlet is opened with a time delay, and the solenoid valve of the other pressure equalizing pipe is opened. Are opened with the time delay, the heating device of the other booster is turned off with the time delay, and the solenoid valve at the outlet of the booster is closed with the time delay. (6) In the above (1), (2), (3), (4) or (5), a heat source having a condenser in a discharge pipe of a compressor and downstream thereof in a primary circulation cycle. A pipe is branched from one of the outlet sides of the side heat exchanger, and is connected to the heating device of the booster via a flow control valve. (7) The above (1), (2), (3), (4), (5)
Or (6) that the primary side pipe of the primary / secondary heat exchange section is branched in the primary side circulation cycle, and the cooler of the booster is configured via a flow rate control valve. Features. (8) In the above (1) and (2), a variable displacement compressor is used as the compressor in the primary circulation cycle, and the operating speed is changed. (9) In the above (1), natural refrigerant is sent from the compressor to the primary / secondary heat exchange section in the primary circulation cycle, and the primary / secondary cycle is sent in the secondary circulation cycle. An indoor heat exchanger is provided downstream of the heat exchange section, and a booster is provided at a lower value thereof. (10) In the primary circulation cycle, the natural refrigerant is sent from the compressor to any one of the heat source side heat exchanger having the condenser and the primary / secondary heat exchange unit via the valve, and the secondary side circulation. In the cycle, a check valve, a booster, and a solenoid valve are provided at lower values of the primary and secondary heat exchangers, and a plurality of valves are interposed between the primary and secondary heat exchangers, the booster. A cooling circuit configured in the order of the indoor heat exchanger and a heating circuit configured in the order of the primary / secondary heat exchange unit, the indoor heat exchanger, and the booster.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Here, an embodiment of the present invention will be described with reference to FIGS. The same parts as those in FIGS. 15 and 16 are denoted by the same reference numerals. In FIG. 1, 1 is a primary refrigerator, 2 is a secondary heat exchanger, and 3 is a secondary pipe. A configuration as shown in FIG. 1 is provided downstream of the primary refrigerator 1 and between the secondary refrigerator and the secondary heat exchanger 2.
That is, a booster 53 is provided below the condensing section of the primary refrigerator 1 via a liquid reservoir 51 and a check valve 52 in order, and the liquid reservoir 51 is provided in parallel with the liquid reservoir 51 and the check valve 52. A pressure equalizing pipe 55 is communicated from an inlet to an inlet of the booster 53 via an electromagnetic valve 54, and an electromagnetic valve 56 is provided at an outlet of the booster 53. A heating device 57 is provided in the booster 53.

Here, the secondary refrigerant which is a natural refrigerant such as CO ₂ radiated and condensed by the refrigerator 1 to the primary side is absorbed by the secondary side heat exchanger 2 to cool the cooled object. The operation of returning to the next refrigerator 1 is the same as that of FIG. 1
Reservoir 5 at a lower value downstream of the condensing section of the next refrigerator 1
The secondary refrigerant is dropped by its own weight in 1 and is stored.
The next refrigerant enters the booster 53 through the check valve 52. In this case, the solenoid valve 54 is open, and the reservoir 51 and the booster 53
Are forcedly equalized so that the secondary refrigerant in the liquid reservoir is introduced into the booster 13 by its own weight.

When the liquid refrigerant is sufficiently stored in the booster 53, the solenoid valves 54 and 56 are closed and the check valve 52 is closed.
And the booster 53 is closed. Here, the secondary refrigerant is heated by the heating device 57 to increase the pressure inside the booster 53. For example, when the heat exchanger 2 is located at a higher position than the booster 53, the liquid refrigerant from the booster 53 is opened by opening the solenoid valve 56 after the pressure inside the booster 53 has increased by about the head difference and the pressure loss. It is pushed out and circulates in the secondary refrigerant circuit. At this time, by operating the heating device 57 until the liquid refrigerant inside the booster 53 drops below the position of the heating device 57 and cannot effectively increase the pressure, the pressure inside the booster 53 is reduced. Is always kept high, and the refrigerant is continuously transported. In addition, by controlling the amount of heating by the heating device 57, the pressure of the booster 53 and thus the amount of secondary refrigerant circulation can be controlled. While the pressure inside the booster 53 is increased and the refrigerant is being conveyed, the secondary refrigerant is not introduced from the liquid reservoir 51 to the pressure booster 53 due to the check valve 52 because the check valve 52 is provided. Is stored.

After the liquid refrigerant inside the booster 53 decreases and the secondary refrigerant cannot be conveyed, it is necessary to close the solenoid valve 56 and store the refrigerant inside the booster 53 again. But,
Since the pressure inside the booster 53 is high, the secondary refrigerant cannot be introduced into the booster through the check valve 52 as it is. In this example, the solenoid valve 54 is opened to forcibly equalize the pressure in the liquid reservoir 51 and the booster 53 without depending on the natural cooling of the refrigerant reservoir 53 as shown in FIG.
The secondary refrigerant inside 1 is introduced into the booster 53 by its own weight. When the refrigerant is sufficiently stored in the booster 53, the electromagnetic valves 56 and 54 are closed, the heating device 57 is operated, and when the pressure increases, the electromagnetic valve 56 is opened to repeat the refrigerant conveyance. The secondary refrigerant conveyed from the booster 53 overcomes the head difference and the pressure loss and is sent to the heat exchanger 2 through the pipe 3. Here, heat is absorbed from the object to be cooled, the secondary refrigerant evaporates and returns to the primary refrigerator 1, where it is radiated and condensed to become a liquid refrigerant, and returns to the liquid reservoir 51 again to complete the cycle. By using this system, when the secondary refrigerant is circulated without using a mechanical pump, more efficient transfer can be performed than in the conventional example. In the present embodiment, the presence of the liquid reservoir 51 is to store the secondary refrigerant in order to prevent the condensing portion of the primary refrigerator 1 from being supercooled. For example, as shown in FIG. In the configuration excluding 51, the equalizing pipe 55 having the solenoid valve 54 is connected to the primary refrigerator 1.
It may be made to communicate with the upstream side of.

As described above, in the example of FIG. 1, when the secondary refrigerant is conveyed without using a mechanical pump, a liquid reservoir or a booster is provided in the middle of the secondary side piping to forcibly equalize the pressure. Thus, the secondary refrigerant can be circulated more efficiently.

FIG. 3 shows a further development of the example shown in FIG. 1, and includes check valves 52a and 52b, boosters 53a and 53b,
The solenoid valves 56a and 56b and the pressure equalizing tube are arranged in parallel to continuously circulate the secondary refrigerant. That is, as shown in FIG.
52b are arranged in parallel and heating devices 57a, 57b are respectively provided.
Are connected to the boosters 53a and 53b having the solenoid valves 54a and 5b, respectively.
4b is connected to the inlet side of the liquid reservoir 51 by a pressure equalizing pipe, and the outlet sides of the boosters 53a and 53b are connected to a solenoid valve 56.
a and 56b are connected to the secondary pipe.

In the configuration shown in FIG. 3, first, the heating device 57a is operated, the solenoid valve 56a is opened and the valve 54a is closed, so that the secondary refrigerant in the booster 53a is circulated by using the above-described method. During this time, the secondary refrigerant condensed by the primary refrigerator 1 is stored in the liquid reservoir 51. By closing the solenoid valve 56b and further opening the solenoid valve 54b,
The secondary refrigerant is stored in the liquid reservoir 51 and the booster 53b that has been equalized. The liquid refrigerant inside the booster 53a is reduced by transport, but when the liquid refrigerant is reduced to some extent, the electromagnetic valve 54b is closed, and the heating device 57b is operated to increase the internal pressure of the booster 53b. Heating device 57
a, 57b and solenoid valves 56a, 56b, 54a, 54
FIG. 4 shows the state of operation of b.

At the timing shown in FIG. 4, for example, the electromagnetic valve 54a of the pressure equalizing pipe is closed, the heating device 57a of the booster 53a is turned on, and the electromagnetic valve 56a is opened with a slight delay in time, and at the same time, the electromagnetic valve 56a is closed and the pressure is increased. Heating device 5 for vessel 53b
7b is turned off and the solenoid valve 54b is opened. at this point,
The secondary refrigerant is sent out from the booster 53a, while the
The coolant is sent from the liquid reservoir 51 to b. Booster 53
Before the liquid refrigerant is conveyed at a, the electromagnetic valve 54b is closed and the heating device 57b is turned on, and at a point slightly later, the electromagnetic valve 54a of the pressure equalizing tube is opened, the heating device 57a is turned off, and the electromagnetic valve 56b is turned off.
Is opened, the solenoid valve 56a is closed, and the secondary refrigerant is
b, and the refrigerant is sent from the liquid reservoir 51 to the booster 53a.

The timing of this operation is as follows.
When the liquid refrigerant is completely conveyed in 3a, the pressure inside the booster 53b is set to such an extent that a pressure difference corresponding to the head difference and the pressure loss in the secondary refrigerant circuit occurs. Considering the heat capacity and supercooling of the liquid refrigerant cooled by the primary refrigerator 1, there is a time lag from when the refrigerant is started to be heated by the heating devices 57a and 57b to when the pressure starts to rise. Solenoid valves 56a, 57a
The time delay until the refrigerant is conveyed when the door is opened can be eliminated. During the delay time when both the solenoid valves 54a and 54b are closed, since the pressures of both the boosters 53a and 53b increase, the boosters 53a and 52b pass through the check valves 52a and 52b.
The refrigerant cannot be introduced into the a and 53b, and the condensed refrigerant is stored in the liquid reservoir 51. After the liquid refrigerant inside the booster 53a has been conveyed, the solenoid valve 56a is closed, and the solenoid valve 56b is opened instead, so that the liquid refrigerant flows from the booster 53b whose pressure has been increased in advance to the heat exchanger 2. The secondary refrigerant is conveyed and can be continuously circulated without interruption. Further, at this time, the solenoid valve 54a is opened to equalize the pressure in the reservoir 51 and the booster 53a, and the liquid refrigerant stored in the reservoir 51 is introduced into the booster 53a. Booster 53b
After the internal liquid refrigerant has been conveyed, the two boosters 5
By changing the roles of 3a and 53b, the refrigerant can be continuously circulated with further development than the above-described example.
In this example, when it is not necessary to provide the liquid reservoir 51, the pressure equalizing pipe inlet may be connected to the upstream side of the primary refrigerator 1 as analogized from FIG.

Thus, in the example of FIG. 3, in addition to the effect of the example of FIG. 1, the operation timing of the solenoid valve and the heating device is optimized as shown in FIG. The refrigerant can be continuously circulated.

In the above description, CO ₂ was used without using a mechanical pump.
Such a refrigerating device that only circulates a natural refrigerant such as a natural refrigerant is used to reduce slow response and heat loss.

Next, primary and secondary refrigeration apparatuses using the transfer apparatus according to the previous example are shown in FIGS. In the drawings following FIG. 5, the same parts as those in FIG. 15 are denoted by the same reference numerals. That is, on the primary side, a compressor 11, a four-way valve 12 for switching a flow path, a heat source side heat exchanger 13 having a fan 14, an expansion valve 15, a primary / secondary heat exchanger 16, an accumulator 1
The primary refrigerant circulates at 7 and the secondary refrigerant circulates at the secondary side with a primary / secondary heat exchanger 16 and an indoor heat exchanger 19 with a fan 20. In this case, the primary refrigerant uses propane and the secondary refrigerant uses CO ₂ .

In the present embodiment, a liquid reservoir 101, a check valve 102, a booster 103 having a heating device 105, and a solenoid valve 104 are arranged in the lower order on the secondary side of the primary / secondary heat exchanger 16 in order. Provided. In FIG. 5, the primary-side refrigerant propane is compressed by the compressor 11 and circulates. During cooling, the refrigerant is condensed and liquefied in the condenser of the heat source side heat exchanger 13 and evaporated in the primary and secondary heat exchangers 16. . On the other hand, on the secondary side, the primary / secondary heat exchanger 16 is used as a condenser. Here, the secondary side carbon dioxide gas refrigerant cooled by the primary refrigerant propane is cooled and liquefied to a liquid reservoir 101, and the check is performed. Booster 10 through valve 102
Fall to 3. When the solenoid valve 104 is closed, the liquefied carbon dioxide gas accumulates in the booster 103 and the heating device 105 is heated when a predetermined amount of carbon dioxide gas accumulates. When the indoor heat exchanger 19 is at a high position, the amount of heating may be such that a pressure difference sufficient to circulate the liquid against the liquid head and the pressure loss is generated. By opening the solenoid valve 104 when a predetermined pressure difference is applied, the liquefied refrigerant is pressure-fed to the indoor heat exchanger 19 without flowing back to the reservoir 101 by the action of the check valve 102, and the room is cooled here. The cycle of evaporating and returning to the primary / secondary heat exchanger 16 and liquefying again is repeated.

At this time, the energization of the heating device 105 is stopped at the same time as the electromagnetic valve 104 is opened, or the energization is stopped for a predetermined time after the electromagnetic valve 104 is opened, and thereafter the energization is stopped. In the former case, the differential pressure acting as the driving force is greatly reduced, and the circulation amount is immediately reduced. In the latter case, however, the heating device 105 is combined with the fact that the heating causes the liquid to flow out of the booster 103 and the liquid refrigerant amount to be reduced. Even if the number of inputs is reduced, the amount of circulation can be kept large and the transport time can be extended. The liquid reservoir 101 is provided in order to prevent the refrigerant from staying in the primary / secondary heat exchanger 16 and overcooling to increase the heating time.
03 alone, the booster 1 even if there is no reservoir 101
03 can be substituted. It is preferable that the heating device 105 is disposed at a lower portion in the booster 103 so that the liquid can be always heated even if the liquid refrigerant is reduced by outflow.

With respect to the refrigerant, the primary-side refrigerant propane is flammable, but the above-mentioned configuration in which the propane is not used indoors but used outdoors reduces the possibility of a fire in case of leakage. Also, the primary refrigerant propane is pressure,
Since the humidity characteristics have almost the same characteristics as the conventional Freon refrigerant R22, the conventional equipment can be used without any design change. Refrigerant carbon dioxide secondary side in the case of (1.2MP _a relative about 7MP _a of example 30 ° C. In R22) pumps used in high-pressure refrigerant, it is necessary to consider pressure resistance, but the above as pumpless This eliminates the movable parts during the cycle and eliminates problems such as failure. Further, since the refrigerant is a high-pressure refrigerant, there is an advantage that the pressure difference, which is the driving force, can be increased even if the amount of heating is small. In addition, since the primary and secondary sides use a natural refrigerant, the system can have a significantly lower global warming potential (GWP) as well as an ozone depletion potential of zero. GWP is CO ₂ = 1, propane =
For 3, R22 = 1700.

FIG. 6 is a modification of FIG. 5, which differs from FIG. 5 in that the discharge gas of the primary compressor is used as the heat source of the heating device 105 of the booster 103. That is, the discharge pipe coming out of the compressor 11 toward the four-way valve 12 is:
After being branched on the way, passing through the flow control valve 110 and the heating device 105, it is communicated with the original discharge pipe. In this case, the flow control valve 110 may be provided in the discharge pipe instead of the branch pipe. Further, as another example, the condenser of the heat source side heat exchanger 13 may be branched from a liquid pipe that has exited. Further, outside air may be sent to the booster 103 instead of the discharge pipe or the liquid pipe. If the booster 103 is provided with a fin, the heat exchange efficiency is increased. The operation in the configuration of FIG. 6 is as follows. When a predetermined amount of liquid refrigerant has accumulated in the booster 103, the flow control valve 110 is opened, and the temperature in the booster 103 is increased with an appropriate amount of discharge gas. When the solenoid valve 104 is opened, the refrigerant circulates through the system. Thereafter, if the solenoid valve 104 is closed at the same time as the flow control valve 110 is closed, the refrigerant accumulates in the booster 103, and the refrigerant can be transported by repeating this operation. The energy on the primary side can be effectively recovered without using wasteful energy as compared with the example of FIG.

FIG. 7 shows a second modification, which differs from the structure shown in FIG. 4 in that the primary outlet pipe of the primary / secondary heat exchanger 16 is branched and a booster is provided in the branch pipe 120. A cooler 121 for cooling 103 and a flow control valve 122 are provided. In FIG. 5, the heating device 105 is turned on and the booster 10 is turned on.
Even if the heating device 105 is turned off after the liquid refrigerant in 3 is delivered, the temperature does not decrease gradually due to the heat capacity of the booster 103. Therefore, both the operating pressure and the temperature tend to increase, and the cooling efficiency decreases. For this reason, in this example, the operating pressure and temperature are maintained at predetermined values by appropriately cooling the booster 103 with the low-temperature refrigerant on the primary side.
That is, when the heating device 105 is turned off,
The temperature of the booster 103 is maintained at a predetermined temperature by the cooler 121 by adjusting the opening degree of the flow control valve 122 of FIG.
22 is closed to prevent the refrigerant from flowing into the cooler 121.

FIG. 8 shows a third modification. The difference from FIG. 5 is that the primary compressor 11 is a variable displacement compressor 11 a using an inverter or the like, and the heating device 105 of the booster 103 is omitted. On the point. In such a configuration, the following operation is performed. The liquefied refrigerant on the secondary side is stored in the booster 103 by operating the variable displacement compressor 11a at a low speed. When a predetermined amount has been accumulated, the primary side compressor 11a is operated at high speed to lower the condensing temperature of the primary / secondary heat exchanger 16 to lower the condensing pressure. The refrigerant is circulated by opening the solenoid valve 104 when a pressure difference sufficient to circulate the refrigerant on the secondary side is obtained before and after the check valve 102.

FIG. 9 shows a fourth modification, which is different from the example of FIG. 5 in that a check valve 102a,
102b, boosters 103a and 103b having heating devices 105a and 105b, and solenoid valves 104a and 104b are connected in parallel. In such a configuration, the following operation is performed. The refrigerant flowing out of the reservoir 101 is supplied to the booster 10 by closing the solenoid valves 104a and 104b.
When a predetermined amount of refrigerant accumulates in the heaters 3a and 103b, one of the heating devices 105a is turned on to increase the pressure to a predetermined pressure or open a solenoid valve 104a after a predetermined time has elapsed. As a result, the refrigerant in the booster 103a is stored in the liquid reservoir 10 by the action of the check valve 102a.
It circulates through the system without backflow to one side. On the other hand, since the heating device 105b is off and the electromagnetic valve 104b remains closed, the refrigerant condensed in the primary / secondary heat exchanger 16 continues to accumulate in the booster 103b via the liquid reservoir 101. The heating device 105b is heated after a lapse of a predetermined time whether the refrigerant amount or the circulation amount in the booster 103a decreases or the refrigerant in the booster 103b reaches a predetermined amount, opens the electromagnetic valve 104b at a predetermined pressure or after a predetermined time, and simultaneously opens the electromagnetic valve. 104a is closed and the heating device 105a is turned off. This causes the refrigerant in the booster 103b to circulate in the system this time,
The refrigerant starts to accumulate inside. In this manner, the refrigerant can be continuously circulated by alternately repeating storage, heating, and ON / OFF of the solenoid valve.

FIG. 10 shows a fifth modification, which is different from FIG. 9 in that the pressure boosters 103a, 103b and the reservoir 101 are connected to the equalizing pipes 141a, 141 via solenoid valves 140a, 140b.
b. This configuration operates as follows. The refrigerant flowing out of the reservoir 101 is supplied to the solenoid valves 104a, 104
b, the boosters 103a, 103b
Accumulate in At this time, the solenoid valves 140a and 140b may be open or closed. When a predetermined amount of refrigerant has accumulated, one of the solenoid valves 105a is heated, and at the same time, the solenoid valve 140a is closed. The solenoid valve 104a is opened after the pressure in the booster 103a rises to a predetermined pressure or after a predetermined time has elapsed. Thereby, the booster 103
The refrigerant in a is circulated in the system without flowing back to the liquid reservoir 101 side by the action of the check valve 102a. On the other hand, the heating device 105b is not heated, the solenoid valve 104b is closed, and the solenoid valve 140b is opened, so that the booster 10
Since the pressure in the reservoir 3b and the pressure in the reservoir 101 are equalized, the liquid in the reservoir 101 continues to fall into the booster 103b by gravity. After that, when the amount of refrigerant in the booster 103a decreases, the amount of circulation decreases, or the refrigerant in the booster 103b accumulates for a predetermined time or a predetermined time has elapsed, the electromagnetic valve 140b is closed and the heating device 105b is turned on. The solenoid valve 104b is opened at a predetermined pressure or after a predetermined time,
4a is closed, the heating device 105a is turned off, and the solenoid valve 140a is opened. Then, the refrigerant in the booster 103b starts to circulate in the system, and the refrigerant starts to accumulate in the booster 103a. When the heating device 105a is turned off, the pressure in the booster 103a does not decrease immediately, but the solenoid valve 140
By turning on a, the liquid reservoir 101 and the booster 103 are turned on.
The pressure of a is equalized, and the liquid refrigerant easily falls. Although the liquid reservoir 101 is provided in FIG. 10 to prevent the primary / secondary heat exchanger 16 from being supercooled, the liquid reservoir 101 may be omitted if there is little possibility of such a possibility. In this case, the pressure equalizing tubes 141a and 141b shown in FIG. 10 can be connected to the secondary upstream side of the primary / secondary heat exchanger 16 as shown in FIG.

FIG. 12 shows a sixth modification. The difference from FIG. 5 is that the indoor heat exchanger 20 and the blower 19 are arranged downstream and downstream of the primary and secondary heat exchangers 16. Further, a booster 103 having a check valve 102 and a heating device 105 is provided at the downstream lower value. Therefore, the check valve 102, the booster 103, and the solenoid valve 104 exist indoors. In such a configuration, the primary system is a four-way valve 12.
Is switched, and the propane refrigerant that has exited the compressor 11 is condensed and liquefied in the primary and secondary heat exchangers 16, throttled by the expansion valve 15, evaporated in the heat source side heat exchanger 13, and returned to the compressor 11. .
On the secondary side, the carbon dioxide gas refrigerant heated and evaporated in the primary / secondary heat exchanger 16 is condensed and liquefied by the indoor air blown from the blower 19 in the indoor heat exchanger 20 therebelow, and the room is heated. Since the solenoid valve 104 is closed, the refrigerant condensed and liquefied in the indoor heat exchanger 20 passes through the check valve 102 and accumulates in the booster 103 further below the check valve 102. If the heating device 105 is turned on when the predetermined amount has been accumulated and the solenoid valve 104 is turned on at the time when the pressure reaches a predetermined pressure, the liquid refrigerant in the booster 103 is sent out and returns to the primary / secondary heat exchanger 16 again. The cycle of being heated and evaporated by the high-temperature refrigerant on the primary side is repeated. By arranging the indoor heat exchanger 20 below the primary and secondary heat exchangers 16, a heating cycle can be configured without a pump in a system using natural refrigerant on both the primary and secondary sides. Further, the amount of heat of the heating device 105 can be effectively used for heating.

FIGS. 13 and 14 are modifications of FIG.
The difference from FIG. 12 is that both cooling and heating can be performed by interposing a three-way valve and a two-way valve in the secondary-side pipeline and switching between them. Primary and secondary heat exchanger 1
A three-way valve A is interposed at the outlet of No. 6 and one is connected to the indoor heat exchanger 20 and the other is connected to the check valve 102. In addition, the indoor heat exchanger 20
Is connected to a check valve 102 via a two-way valve D on one side and to a three-way valve B provided downstream of the solenoid valve 104 via a two-way valve D. Check valve 102, booster 103, solenoid valve 104,
The pipe connected to the three-way valve B is a three-way valve C disposed in a pipe on the outdoor side, one of which is a pipe between the three-way valve A and the indoor heat exchanger 20, and the other is a primary / secondary heat exchanger. Connected to the vessel 16 to form a closed cycle. With this configuration, the following operation is performed. At the time of heating, the three-way valves A, B, and C are positioned as shown in FIG. 13 and the two-way valve D is opened, whereby heating can be performed as in FIG. On the other hand, during cooling, the three-way valves A, B, C
By switching as shown in FIG. 4 and closing the two-way valve D, the cycle on the secondary side becomes the primary / secondary heat exchanger 16, the three-way valve A, the check valve 102, the booster 103, the solenoid valve 104, the three-way valve. B,
The circuit of the indoor heat exchanger 20, the branch point E, the three-way valve C, and the primary / secondary heat exchanger 16 is configured to form a cooling cycle. By switching the three-way valves A, B, C and the two-way valve D, a natural refrigerant system using propane on the primary side and carbon dioxide on the secondary side can be implemented for both cooling and heating without a pump.

[0033]

As described above, the present invention has the following effects. (1) In the secondary circulation cycle, using a natural refrigerant, a booster is provided via a check valve that forms a flow path in only one direction at a position below the primary and secondary heat exchange units, By providing an electromagnetic valve on the outlet side of this booster to control the opening and closing of the flow path of the natural refrigerant, the ozone depletion potential is zero, the global warming potential is extremely small, and even if there is a leak, propane or CO ₂ can be reduced. By using this, the problems of watering and explosion are extremely reduced, and further, the heat loss can be reduced without using a mechanical pump, and the response can be made slower than before. (2) Since the liquid reservoir is provided between the primary / secondary heat exchange section and the check valve, it is possible to suppress overcooling of the primary / secondary heat exchange section. (3) In the secondary circulation cycle, the primary and secondary
By providing a pressure equalizing pipe having an electromagnetic valve for controlling the opening and closing of the flow path in parallel with the check valve between the next heat exchange unit and the booster, it is possible to surely and smoothly drop the refrigerant to the booster. Can be. (4) By providing two sets of pressure equalizer tubes each having a solenoid valve in parallel with the check valve on the inlet side and a booster having an electromagnetic valve on the outlet side in parallel, alternate on / off control of each set is provided. This enables continuous delivery of the refrigerant. (5) Close the solenoid valve of one pressure equalizing tube, turn on the heating device provided in the booster, open the solenoid valve at the booster outlet with a time delay, and open the solenoid valve of the other pressure equalizing tube with the time delay. Further, the heating device of the other booster is turned off with the time delay, and the solenoid valve at the outlet of the booster is closed with the time delay, so that heating is performed even after the solenoid valve at the outlet of the booster is opened. Can be expanded. (6) The pipe is branched from either the discharge pipe of the compressor in the primary circulation cycle or the outlet side of the heat source side heat exchanger downstream of the compressor and having the condenser, and the flow is controlled through the flow control valve. By communicating with the heating device of the booster, the energy can be effectively used by utilizing the primary energy for the heating device. (7) In the primary circulation cycle, the primary pipe of the primary / secondary heat exchange section is branched, and the cooler of the booster is configured via a flow rate control valve. The operating pressure and temperature were not increased by the low-temperature refrigerant on the side. (8) Within the primary circulation cycle, the compressor uses a variable displacement compressor and changes the operating speed, so that a pressure difference is created by increasing the compressor rotation speed. No heating device is required. (9) The natural refrigerant is sent from the compressor to the primary / secondary heat exchange section in the primary circulation cycle, and downstream of the primary / secondary heat exchange section in the secondary circulation cycle. Equipped with an indoor heat exchanger and a booster at the lower value,
Heating operation with natural refrigerant is possible without pump,
Also, the heat energy of the heating device can be taken into heating. (10) In the primary circulation cycle, the natural refrigerant is sent from the compressor to any one of the heat source side heat exchanger having the condenser and the primary / secondary heat exchange unit via the valve, and the secondary side circulation. In the cycle, a check valve, a booster, and a solenoid valve are provided at lower values of the primary and secondary heat exchangers, and a plurality of valves are interposed between the primary and secondary heat exchangers, the booster. By switching between a cooling circuit configured in the order of the indoor heat exchanger and a heating circuit configured in the order of the primary and secondary heat exchange units, the indoor heat exchanger, and the booster, it is possible to perform both cooling and heating. .

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an example of a basic embodiment of the present invention.

FIG. 2 is a configuration diagram when a liquid reservoir is omitted in FIG.

FIG. 3 is a configuration diagram in which two sets of the configuration of FIG. 1 are arranged in parallel.

FIG. 4 is a waveform chart of each part in FIG. 3;

FIG. 5 is a configuration diagram also showing a primary circulation cycle.

FIG. 6 is a configuration diagram of a first modified example of FIG. 5;

FIG. 7 is a configuration diagram of a second modification of FIG. 5;

FIG. 8 is a configuration diagram of a third modification of FIG. 5;

FIG. 9 is a configuration diagram of a fourth modified example of FIG. 5;

FIG. 10 is a configuration diagram of a fifth modification of FIG. 5;

FIG. 11 is a configuration diagram of a modified example of FIG. 10;

FIG. 12 is a configuration diagram of a heating example according to FIG. 5;

FIG. 13 is a configuration diagram at the time of heating in the cooling / heating combined example shown in FIG. 5;

FIG. 14 is a configuration diagram at the time of cooling in the example of both cooling and heating shown in FIG.

FIG. 15 is a configuration diagram of a conventional example corresponding to FIG.

FIG. 16 is a configuration diagram of a conventional example corresponding to FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Primary-side refrigerator 2 Secondary-side heat exchanger 11, 11a Compressor 16 Primary / secondary heat exchanger 20 Indoor heat exchanger 51,101 Liquid reservoir 52, 52a, 52b, 102, 102a, 102b
Check valve 53, 53a, 53b, 103, 103a, 103b
Boosters 54, 56, 54a, 54b, 56a, 56b, 10
4, 104a, 104b, 140a, 140b Solenoid valve 110, 122 Flow control valve

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Harunobu Mizukami 1 Takamichi, Iwazuka-cho, Nakamura-ku, Nagoya-shi, Aichi, Japan Nagoya Research Laboratory, Mitsubishi Heavy Industries, Ltd.

Claims (10)

[Claims] In the secondary circulation cycle, a natural refrigerant is used, and a booster is connected to a booster through a check valve that forms a flow path in only one direction at a position below a primary / secondary heat exchange section. A refrigerating apparatus provided with an electromagnetic valve for controlling opening and closing of the flow path of the natural refrigerant at an outlet side of the pressure increasing device. 2. The refrigeration system according to claim 1, wherein a liquid reservoir is provided between said primary / secondary heat exchange section and a check valve. 3. The method according to claim 1, wherein the first circulation cycle includes:
The refrigerating apparatus according to claim 1 or 2, further comprising a pressure equalizing pipe provided with an electromagnetic valve that controls opening and closing of the flow path in parallel with the check valve between the secondary / secondary heat exchange unit and the booster. 4. The refrigerating apparatus according to claim 3, wherein two sets each comprising a pressure equalizer having an electromagnetic valve in parallel with the check valve on the inlet side and a booster having an electromagnetic valve on the outlet side are provided in parallel. . 5. The solenoid valve of one of the pressure equalizing tubes is closed, the heating device provided in the booster is turned on, the solenoid valve at the outlet of the pressure equalizer is opened with a time delay, and the solenoid valve of the other pressure equalizing tube is closed with the time delay. 5. The refrigerating apparatus according to claim 4, wherein the refrigerating apparatus is opened with the time delay, the heating device of the other booster is turned off with the time delay, and the solenoid valve at the booster outlet is closed with the time delay. 6. A pipe is branched from one of a discharge pipe of a compressor and a downstream side of a heat source side heat exchanger having a condenser in a primary side circulation cycle and a flow control valve is provided. The refrigeration apparatus according to claim 1, 2, 3, 4, or 5, wherein the refrigeration apparatus communicates with a heating device of the booster via a heating device. 7. A cooler for the booster via a flow control valve, wherein a primary pipe of the primary / secondary heat exchange section is branched in a primary circulation cycle. , 2,
7. The refrigeration apparatus according to 3, 4, 5, or 6. 8. The refrigeration system according to claim 1, wherein the compressor is a variable capacity compressor in the primary circulation cycle and the operating speed is changed. 9. A natural refrigerant is sent from a compressor to a primary / secondary heat exchange section in a primary circulation cycle, and is sent to the primary / secondary heat exchange section in a secondary circulation cycle. 2. The refrigeration apparatus according to claim 1, further comprising an indoor heat exchanger downstream of the indoor heat exchanger, and a booster at a lower value thereof. 10. A natural refrigerant is sent from a compressor to a heat source side heat exchanger having a condenser and to a primary / secondary heat exchange section via a valve in a primary side circulation cycle. In the side circulation cycle, a check valve, a booster, and a solenoid valve are provided at lower values of the primary and secondary heat exchange units, and a plurality of valves are interposed between the primary and secondary heat exchange units. A refrigeration apparatus that switches between a cooling circuit configured in the order of a booster and an indoor heat exchanger, and a heating circuit configured in the order of a primary / secondary heat exchange unit, an indoor heat exchanger, and a booster.