JPS6321447A - Refrigeration cycle - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

[Object of the Invention] (Industrial Application Field) The present invention relates to a refrigeration cycle, and particularly to a refrigeration cycle equipped with a heat storage device. (Prior technology) Attempt to install a heat storage device in the frozen cycle and temporarily utilize the heat stored in this phantom heat storage device to improve performance.

[This has been done for a long time. As a conventional frozen T-Nicle of this kind, there is, for example, the one shown in FIG. 7 and described in Japanese Patent Publication No. 1983-20023. This refrigeration cycle number, when the compressor is in refrigeration operation, the i! ! ! The refrigerant that has become wet and high pressure is guided to the heat storage 2S2 and stored therein, and this heat storage is used during defrosting operation to melt frost and ice on the evaporator surface. That is, during refrigeration operation, the refrigerant is sequentially heated to a pressure of 1i!, as shown by the solid arrows. tfi 1, four-way valve 3, regenerator 2, condenser 4, depressurizer 7, and evaporator 8, the flow is returned to the compression line 1, and during this cycle, the regenerator 2 absorbs the heat from the high-temperature refrigerant and stores it. On the other hand, during defrosting operation, the four-way valve 3 is switched to switch the flow path, and the refrigerant is sequentially passed through the compressor 1, the four-way valve 3, the evaporator 8, the bypass pipe B, and the heat storage 2 as shown by the broken line arrow. The refrigerant flows back to the compressor 1 , defrosts the evaporator 8 , exchanges heat, and liquefies the refrigerant, which undergoes heat exchange in the heat storage device 2 , vaporizes, and returns to the compressor 1 . Note that numerals 23, 24, and 25 are check valves. In this way, during the freezing operation, the refrigerant absorbs heat from the high temperature refrigerant and stores it, while during the defrosting operation, it passes through the evaporator and releases the stored heat to the defrosted refrigerant for heating. (Problems to be Solved by the Invention) However, in the above-mentioned refrigeration cycle, the heat storage in the heat storage device 2 is used to improve defrosting, but the refrigeration cycle in which the heat storage in the heat storage device is most desired to be used is There is a problem that when the heat exchanger on the user side (high compression) starts up, it is not used at all.In addition, during heat storage, the pipe A from the compression 811 to the heat storage unit 2 becomes high pressure, and the refrigerant flows into the bypass pipe B. In other words, there is a problem that the bypass pipe 8 from the check valve 23 to the branch point of the pipe A becomes a liquid pool during heat storage. The objective is to create a 1-night refrigeration system that can effectively utilize the heat stored in the heat storage device at the start-up of the heat exchanger (condenser) on the user side of the refrigeration cycle, and eliminate liquid accumulation in each pipe. [Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention provides a compressor, a condenser,
In a refrigeration cycle in which a pressure reducing device and an evaporator are successively connected through a pipe line, a heat storage device is interposed between the discharge side of the compressor d and the condenser, and a bypass pipe is connected at one end to the condenser and the pressure reducing device. and the other end is connected between the pressure reducing device and the evaporator via the heat storage device, and the bypass pipe is branched at the exit side of the heat storage device to connect the bypass pipe to the compressor. It is characterized by providing a branch pipe connected to the suction side. (Function) According to the present invention, the refrigerant pressurized by the compressor passes through the heat storage device during the start-up operation of the user-side heat exchanger (condenser) of the refrigeration cycle that utilizes the heat stored in the heat storage device. The refrigerant passes through the condenser, where heat exchange takes place, and the refrigerant that flows into the bypass pipe through the condenser is heat exchanged and heated in the regenerator, and then flows back to the compressor through the evaporator, where it is compressed. By increasing the temperature on the machine suction side, the condenser can perform heating with a large output. In addition, heat dissipation in the evaporator can be prevented by returning the refrigerant discharged from the heat storage device during start-up operation directly from the branch port without passing through the evaporator. (Actual Droplet Example) Hereinafter, an example of the refrigeration cycle according to the present invention will be described with reference to FIGS. 1 and 2. Fig. 1 shows a refrigeration cycle diagram of an air conditioner. In the figure, 1 is a compressor, 2 is a heat storage device, 4 is a heat exchanger (condenser) on the user side, and for example, indoor heat exchanger 11A5.7 is a pressure reducing device. ,
8 is a heat exchanger (evaporator) on the heat source side, for example, an outdoor heat exchanger. The heat storage device 2 is made of a heat storage material 2B filled therein, and in this embodiment, for example, paraffin 115° (melting point 45° C.) is filled in the heat storage material 2A. The heat of the refrigerant compressed by the compressor 1 to a high temperature and high pressure is received through the refrigerant pipe 2A and stored, and the heat can be stored at a high temperature in the refrigeration cycle. Further, a bypass pipe B8 is provided between the indoor heat exchanger 4 and the outdoor heat exchanger 8, one end of this bypass pipe is connected between the indoor heat exchanger 4 and the pressure reducing device 7, and the other end is connected between the indoor heat exchanger 4 and the pressure reducing device 7. is connected between the upper knee pressure reducing device 7 and the indoor heat exchanger 8 via the heat storage device 2, and an on-off valve 5. is connected to the bypass pipe Ba. A pressure reducing device 6 and a refrigerant distribution 02D are interposed. Further, the bypass pipe B8 has a branch pipe B that branches off after coming out of the heat storage device 2 and is connected to the suction side of the compressor 1, and a valve 9 is installed in this branch pipe B. has been done. The indoor/outdoor heat exchangers 4 and 8 are each equipped with an indoor fan (condenser fan) 12 and an outdoor fan (evaporator fan) 13, and the heat storage device 2 has a heat storage temperature sensor +J that detects its internal temperature. (For example, Thermister, etc.) 1
0. Next, the operation of the refrigeration cycle of the air conditioner according to the present invention configured as described above will be explained. First, the indoor fan 12 and outdoor fan 1 in each mode
3. Each operation will be explained based on the following table showing each state of the on-off valve 5.9 and the pressure reducing device 7. The on-off valves 5 and 9, the pressure reducing device 7, the indoor fan 12, and the outdoor fan 13 are controlled by the IT and IJ control device 20 as shown in the following table, and the user selects the operation selection switch (not shown) between heat storage mode and normal operation. set. Also, the pressure reducing device 7
An automatic humidity expansion valve may be used, but it is preferable to use an automatic humidity expansion valve.
The electric expansion valve described in Japanese Patent No. 170653 is suitable. The pressure reducing device 7 can perform so-called superheat control using the temperature sensors 17 and 18 so that the difference between the evaporation temperature and the suction temperature of the compressed portion 1 is constant. (1) Heat storage operation When the user sets an operation selection switch (not shown) to heat storage operation, the operation mode becomes "heat storage". That is, the refrigerant pressurized by the compression l111 is circulated to the compressor 1 via the heat storage device 2, the indoor heat exchanger 4, the pressure reducing device 7, and the outdoor heat exchanger 8. During this circulation, heat is stored in the heat storage device 2, and in this embodiment, when the heat storage temperature sensor 10 is 50°C or lower, the compressor 1 is turned ON, and when the temperature is 55°C or higher, the compressor 1 is turned OFF. control. (2) Normal operation When the user sets normal operation using an operation selection switch (not shown), the heat storage utilization heating mode or heating heat storage mode is automatically selected depending on the temperature in the heat storage tank 2A. In this embodiment, for example, when the temperature inside the heat storage tank 2A is 10° C. or higher, a "thermal storage utilization heating mode" is started in which high heating capacity can be achieved by using the heat amount of the heat storage material 2B. Conversely, when the rM degree of the heat storage tank 2A is 10° C. or less, high heating capacity operation using heat storage is not possible, so the operation is in the "heating heat storage mode". First, the case where heating operation using heat storage is first started will be explained. <2>-■ Heating using heat storage (heating start-up) mode When heating operation is not required, heat is stored in the heat storage device 2, and the heat is used to quickly provide a large output at the time of heating start-up@
It is a driving operation. As shown in the above table, when the on-off valve 5 and the on-off valve 9 provided in the branch pipe B are opened, the pressure reducing device 7 is closed, and the outdoor fan 13 is turned off, the refrigeration cycle shown by the solid line arrow in Fig. 1 starts. The refrigerant compressed by the compressor 1 is transferred to the indoor heat exchanger 4 via the heat storage device 2.
Here, heat exchange takes place. The refrigerant liquefied after passing through the indoor heat exchanger 4 passes through an on-off valve 5 and a pressure reducing device 6, and undergoes heat exchange in the heat storage device 2, where it is heated. The refrigerant heated in the heat storage device 2 flows into the branch pipe Bb, passes through the on-off valve 9, and is compressed! 11. Here, since the temperature of the heat storage material 2B is high, the refrigerant evaporates here. Since the evaporation temperature of the refrigerant becomes higher, the suction pressure of the compressor 1 also becomes higher, and the amount of refrigerant circulated increases, so that the indoor heat exchanger 4 can perform heating at once with a large output. Also, in this case, a branch pipe B was provided in the bypass Ta B a connecting between the indoor heat exchanger 4 and the outdoor heat exchanger 8, and this branch pipe B was connected to the compressed component 1 suction side. ,
In the heating mode using heat storage, which is applied at the start of heating, it is possible to prevent heat radiation loss to the outdoor heat exchanger 8, and also avoid pressure loss. In the above embodiment, the pressure reducing device 7 was closed, but the pressure reducing device 7
In this case, the outdoor fan may be turned on to absorb heat from the outside air. Further, although the on-off valve 9 is always open in the heating start-up mode, the on-off valve 9 may be controlled to open or open based on the detected value of the heat storage temperature sensor 1o provided in the heat storage device 2. In other words,
When the heat storage temperature sensor 10 of the heat storage device 2 is 15° C. or lower, the on-off valve 9 is closed and the refrigerant is controlled to flow into the outdoor heat exchanger 8. That is, in Fig. 2, the temperature of the heat storage temperature is TH
C, and the heat radiation start temperature in the out-of-town heat exchanger 8 is T as the initial setting temperature. shall be. Here, To is, for example, 15°C
shall be. When the operation starts, T++C and T. Compare with (step ■). And T1. If Io≧To, open the on-off valve 9 (step ■)'IIc<T. If so, close the on-off valve 9 (step ■). In this case, when the on-off valve 9 opens, the outdoor fan 13 is at 0FFL,
, when the on-off valve 9 is closed, it is controlled to be turned on (if the refrigerant is flowed through the pressure reducing device 7 and superheat control is performed, the outdoor fan 13 is turned on). The Mollier diagram at the start of heating mentioned above is shown in FIG. 3, and A and B shown in FIG.
, C, and E correspond to each part A, B, C, and E in FIG. Therefore, switching between the heat storage utilization heating mode and the heating/heat storage U-do is as shown in the following table: heat storage sensor 10 temperature 11 (d).
and set value <TI)'), where:
Tp is, for example, 10'C. If the heating operation using heat storage is continued, the temperature of the heat storage tank 2A decreases, and for example, when the temperature of 2A becomes below Tp, the "heating heat storage operation mode J" (described later) is activated.
（２）－〇）に（２）－■ l! 1 chamber/thermal storage mode In the heating/thermal storage mode in which heating continues and heat is stored during that time, the refrigerant pressurized by the compressor 1 is transferred to the heat storage 2.
Indoor heat exchanger 4, pressure reduction device 7, outdoor heat exchanger 8
It is returned to the compressor 1 through the If the heating operation continues in this manner, frost will form on the outdoor heat exchanger 8 if the outside temperature is low. For this reason, it is necessary to perform defrosting operation. In addition, switching between "heat storage mode" and "heating/heat storage mode J" may be performed automatically by comparing the room temperature (TXN) and the indoor nermostat setting value (T, ) as shown in the following table. In that case, the heat storage operation described in (1) above is entered, but if T>T1Na') during the heat storage operation, the heating heat storage operation is entered.At that time, if it is necessary to further improve the start-up, the heat storage operation of the mountain heat tank 2A is started.
If the temperature is 10°C or higher, heat storage utilization operation may be started. Next, I will explain about the defrosting operation mode. (2)-■ Defrosting mode In the mode in which the outdoor heat exchanger is defrosted, the detected value of the temperature sensor 6 installed at the heating side inlet of the outdoor heat exchanger 8 is set to the set value during the heating heat storage operation. (for example, −15° C.) or lower, defrosting is started. In this case, the fact that a predetermined period of time (for example, 40 minutes) has elapsed since the previous defrosting is also a condition for starting defrosting. Then, when the detected value of the temperature sensor 16 is equal to or higher than the set value (for example, 10° C.), snow removal is completed and the heating heat storage operation described above is started. Since the on-off valve 5 is open in the defrosting mode, the refrigerant path passes through the compressor 1 and the heat storage 2 as shown by the broken line arrow in FIG.
, the indoor heat exchanger 4, the on-off valve 5, the pressure reducing device 6, the outdoor heat exchanger 8, and the compressor 1 form a loop, and the heat stored in the heat storage device 2 is effectively used for defrosting. Then, during defrosting, defrosting can be performed while continuing to warm the air. In addition, the Mollier diagram at the time of defrosting mentioned above is shown in Fig. 4, and in Fig. 4 J3('' is Δ, B. C, D, E are each part J3 in Fig. 1 △, B, C. It corresponds to D and E. In the example shown in Fig. 1, the refrigeration cycle similar to air conditioning only for heating was explained, but as shown in Fig. 5, a heat pump type air conditioning cycle capable of heating and cooling is explained. In the refrigeration cycle of the conditioner
The present invention is applicable. That is, a temperature sensor 31° 32° is installed near the indoor heat exchanger 4.
A cooling cycle is made possible by providing a check valve 11 in the bypass pipe B and further interposing a four-way valve 3 between the heat storage device 2 and the indoor heat exchanger 4. In the embodiment shown in FIG. 3, the cycle other than the cooling mode is similar to that of the previously described embodiment, so only the "cooling mode" will be explained. In the cooling mode, the refrigerant pressurized by the compressor 1 passes through the heat storage device 2 to the four-way valve 3, the outdoor heat exchanger 8, and the pressure reducing device 7.
, and is recycled to the compression chamber 1 via the indoor heat exchanger 4. Heat is also stored in the heat storage device 2 during this cooling operation. In addition, the on-off valve 5
, 9 are closed, but at least one of the on-off valves 5, 9 may be opened to allow the refrigerant in the bypass pipe B to return. In the embodiment illustrated in FIGS. 1 and 5 described above, the pressure reducing device 7 is an electric 8-inflation valve described in Japanese Patent Application Laid-Open No. 59-170653, but the pressure reducing device 7 is an automatic temperature control valve. If the on-off valve 21 is configured as an expansion valve as shown in FIG. 6(a), the refrigerant flowing into the pressure reducing device 7 can be completely shut off. That is, in FIG. 6(a), an on-off valve 21 is provided immediately upstream of the pressure reducing device 7, and when the on-off valve 5 is opened, the on-off valve 21 is closed. It is better to completely shut off the automatic temperature expansion valve 22 as shown in Fig. 6(b).
It is also possible to have a configuration in which the pressure reducing device 7 (22) is partially passed through. [Effect of charging] As is clear from the description of the embodiments, according to the present invention, the high temperature refrigerant pressurized by the compressor is heat-exchanged in the heat storage device, and the heat is stored in the heat storage device. At the start-up of the heat exchanger (condenser) on the user side of the cycle, the refrigerant that has liquefied through the condenser is guided to the heat storage device via the bypass pipe. :S
Because it exchanges heat with the hot heat storage material, the evaporation temperature increases and the suction pressure of the compressor increases, allowing a large output per unit time to be exerted when the user-side heat exchanger (condenser) of the refrigeration cycle starts up. Further, according to the present invention, since the bypass pipe is connected to the low pressure side between the evaporator and the pressure reducing device, it is possible to prevent liquid from accumulating in the bypass pipe. Furthermore, according to the present invention, a branch pipe is provided that branches the bypass pipe at the outlet side of the heat storage device and connects it to the suction side of the compressor, so that during heat storage utilization operation, the refrigerant is transferred from the condenser to the heat storage device for heat exchange. After performing this, it can be directly returned to the compressor, thereby preventing heat radiation loss from the evaporator and avoiding pressure loss in the evaporator. Furthermore, during defrosting, the refrigerant can be guided from the condenser to the evaporator after heat exchange via the heat storage device, and defrosting can be performed while the heating cycle is in progress, making continuous heating possible.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of a refrigeration cycle according to the present invention, FIG. 2 is a diagram showing a flowchart of the refrigeration cycle,
Figure 3 is a Mollier diagram of the same refrigeration cycle during heating using heat storage, Figure 4 is a Mollier diagram of the same refrigeration cycle during defrosting,
FIG. 5 is a diagram showing another embodiment of the present invention; FIG. 6(a),
(b) is a diagram not showing a modification of the present invention, and FIG. 7 is a diagram showing a conventional refrigeration cycle. 1...Compressor, 2...Regenerator, 3...Four valve, 4
... Indoor heat exchanger, 5... Opening/closing valve, 6, 7... Pressure reducing device, 8... Outdoor heat exchanger, 9... Opening/closing valve, 1o
...Temperature sensor, 12...Indoor fan, 13...
outdoor fan. Applicant's agent Sato - Male 1st eye i (1ntano kL°) i
(Jung 4t°) 3rd eye, 4th figure

Claims (1)

[Claims] 1. In a refrigeration cycle in which a compressor, a condenser, a pressure reducing device, and an evaporator are sequentially connected through a pipe line, a heat storage device is interposed between the discharge side of the compressor and the condenser. At the same time, one end of the bypass pipe is connected between the condenser and the pressure reduction device, and the other end is connected between the pressure reduction device and the evaporator via the heat storage device, and the bypass pipe is further connected to the pressure reduction device and the evaporator. A refrigeration cycle characterized in that a branch pipe is provided that branches at the outlet side of the heat storage device and connects to the suction side of the compressor. 2. The branch pipe is provided with an on-off valve, and by opening and closing this on-off valve, the refrigerant is routed directly from the regenerator to the suction side of the compressor via the evaporator and the refrigerant is connected directly to the compressor. A refrigeration cycle according to claim 1, characterized in that the system is switched to a system leading to a suction side.