JPS6058382B2 - Refrigeration equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vapor compression type refrigeration system that utilizes the latent heat of a refrigerant, and particularly relates to an improvement of a refrigerant flow rate control device.

FIG. 1 shows an example of a refrigerant cycle of a conventional refrigeration system, and FIG. 2 shows the structure of a pressure reducing device.

In FIG. 1, 1 is a compressor, 2 is a condenser, 3 is a capillary tube, and 4 is an evaporator. are connected sequentially to form a refrigeration system. Further, 5 is a flow rate adjustment valve, 6 is a valve lift adjustment device, and 7 is a heat exchange section. In FIG. 2, 3 is a capillary tube, 8 is a pipe, and 9 is a heat insulating material. In such a conventional refrigeration system, refrigerant gas that has become high temperature and high pressure in the compressor 1 is cooled and liquefied in the condenser 2, becomes low temperature and low pressure in the capillary pressure reducing device 3, and is guided to the evaporator 4.

When the refrigerant liquid is gasified in the evaporator 4, it absorbs heat from the surroundings and performs freezing. After this, the refrigerant gas is transferred to the compressor 1
is inhaled. It is known that in such a refrigeration system, the appropriate flow rate of refrigerant varies depending on the evaporation temperature, and normally, as the evaporation temperature increases, a larger flow rate of refrigerant is required.

For example, the temperature at the evaporator inlet and outlet is measured, and the capillary tube is adjusted so that the evaporator outlet temperature is slightly higher than the inlet temperature, that is, the refrigerant is completely gasified at the evaporator outlet and slightly superheated. By adjusting the amount of cooling, an appropriate refrigerant flow rate can be maintained at all times. By the way, as shown in FIG. 3, the relationship between the cooling amount and the refrigerant flow rate is such that as the cooling amount increases, the refrigerant flow rate increases.

This is because the gas content in the two-phase flow of refrigerant generated in the capillary tube decreases as the amount of cooling increases, so fluid resistance decreases and the refrigerant flow rate increases. Utilizing this characteristic, in conventional equipment, for example, the evaporator 4
Based on the temperature at the inlet and outlet, the valve lift control device 6 controls the valve lift of the flow rate adjustment valve 5 to adjust the flow rate of the refrigerant from the condenser, and the cooled refrigerant is passed through the heat exchanger section 7 into the capillary tube 3. The flow rate of the refrigerant through the capillary was controlled by increasing or decreasing the amount of cooling the refrigerant. Conventional refrigeration equipment was constructed as described above, but the capillary tube 3 is coiled and attached to the vibrator 8, and the condenser outlet vibrator and evaporator inlet vibrator are connected to the condenser outlet vibrator and evaporator inlet vibrator with different diameter tubes. The production was troublesome as it took a lot of time and effort to narrow down the parts.

Moreover, the contact between the capillary tube 3 and the vibe 8 is insufficient,
In some cases, the performance was not sufficient. Further, there were drawbacks such as the capillary tube's winding diameter cannot be made too small and the capillary tube being long, the pressure reducing device becomes large.
This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and uses a pressure reducing device in which an insert with a spiral groove is inserted so as to be in close contact with the inner wall of the pipe, and the refrigerant flowing inside the groove is reduced. The object of the present invention is to provide a refrigeration device that can cool from the outside and control the flow rate.

Embodiments of the present invention will be described below with reference to the drawings. Fig. 4 is a block diagram of one embodiment of the same, and Fig. 5 is a diagram showing the structure of the decompression device. In these figures, the same parts as in Figs. 1 and 2 are given the same reference numerals. The explanation will be omitted. In FIG. 4, 10 is a pressure reducing device having the structure shown in FIG. 5, and 11 is a heat exchange section.

Further, in FIG. 5, 12 is a spiral groove 1 on the outer periphery.
3, and is inserted in close contact with the inner wall of the vibrator 8. In the refrigeration system configured as described above, the liquid refrigerant from the outlet of the condenser 2 is made low temperature and low pressure by the flow rate regulating valve 5, and is led to the heat exchange section 11, and then the liquid refrigerant is brought to the pressure reducing device 1.
It is possible to cool the refrigerant flowing through the groove 13 of 0.

Therefore, by controlling the amount of low-temperature refrigerant flowing into the heat exchanger 11 by increasing or decreasing the valve lift of the flow rate control valve 5 with the valve lift control device 6, the amount of cooling of the refrigerant in the pressure reduction device 10 can be adjusted, and therefore the pressure reduction The flow rate of refrigerant through device 10 can be controlled. These functions are similar to conventional devices, but in the device of the present invention, in the pressure reducing device shown in FIG.
The heat exchange efficiency is good, and the connection is easy because the vibe 8 can be made to have the same diameter as the condenser outlet pipe and the evaporator inlet pipe.
It can be further downsized.

In the above embodiment, the inlet of the flow control valve was connected to the condenser outlet, and the outlet was connected to the evaporator inlet. This can be done anywhere that low temperature refrigerant can be obtained, such as bypassing the outlet or even part of the suction pipe.

Further, the outlet of this refrigerant does not necessarily have to be the evaporator inlet, but may be any part where the pressure is lower than the flow rate regulating valve inlet, such as the compressor suction, the evaporator middle, the pressure reducing valve middle, etc. Further, in the above embodiment, the case where the inserted insert has a groove is shown, but the same effect can be obtained by using a pressure reducing device having a spiral groove 13 in the inner wall of the pipe as shown in FIG.

Furthermore, by making a bag-shaped cavity 14 inside the insert 12 and inserting a heat insulating material with a small heat capacity therein, the heat capacity of the pressure reducing device 10 is reduced, and the flow rate can be controlled with good responsiveness. This also applies to the insert 12 having the spiral groove 13 shown in Figure M5. Further, as shown in FIG. 7, a double pipe-shaped flow path 15 is provided so as to surround the pressure reducing device 10 having the spiral groove 13, and the double pipe and the pressure reducing device 10 are further provided.
Even in an integrated device with a small hole 16 that communicates with the outlet of 0, the low temperature refrigerant guided from the vibrator 17 and the refrigerant in the spiral groove 13 of the pressure reducing device 10 can exchange heat in the double pipe section 15. The same effect can be achieved.

In addition, in this device, the double tube part does not necessarily have to cover the whole spiral groove, but may cover only a part of it. Further, the small holes 16 may be opened not at the outlet of the pressure reducing device but at a part of the insert groove 13, or may be plural. Furthermore, as shown in Figure 8,
A through hole 18 is made inside the insert to pass through the entrance and exit,
A vibrator 17 through which low-temperature refrigerant flows is connected from the pressure reducing device inlet side to guide the low-temperature refrigerant into the through hole 18, and the spiral groove 13,
The refrigerant inside may be cooled.

Note that in this device, the through hole 18 may have any shape, and does not need to have a uniform cross-sectional shape. Furthermore, performance can be further improved if heat transfer is promoted by fin-processing the through-hole as shown in FIG. 9 or by inserting a spiral tape. Moreover, even if the through hole 18 is not provided inside the insert, a bag-shaped cavity is provided inside the insert from the pressure reducing device inlet side, and this cavity communicates with a part of the groove to allow the low-temperature refrigerant to flow out there. It may be configured as follows.

Although the above example shows a simple refrigeration system, it is also effective to apply the present invention to a heat pump system in addition to this simple refrigeration system.

That is, as shown in FIG. 10, the complicated circuit of a conventional heat pump equipped with a four-way switching valve 20, indoor/outdoor heat exchangers 21, 22, check valves 23, etc., is replaced by the pressure reducing device shown in FIG. In this case, the pressure reducing device shown in FIG. 11 to 13 is used, and in the case of using the pressure reducing device shown in FIG. This can be accomplished more easily. In addition, the solid line arrow in the figure indicates the heating circuit, and the dotted line arrow indicates the cooling circuit. It goes without saying that the present invention can also be applied to other refrigeration systems such as a multistage refrigeration cycle and a multistage cascade cycle, and the same effects can be achieved even when the present invention is equipped with auxiliary equipment such as an oil separator and a dryer. Further, these pressure reducing devices do not necessarily need to be used alone, and can be used in combination with other pressure reducing devices to achieve even more accurate control. In addition, the flow rate of the low-temperature refrigerant can be controlled not only by a flow rate adjustment valve that changes the valve lift, but also by adjusting the input of the electric heater with the configuration shown in Figure 17 and the structure shown in Figure 18. Any device that can control the flow rate, such as a device that adjusts the flow rate or liquid volume, may be used.

In FIGS. 17 and 18, 24 is a flow rate adjustment device, 25 is an electric input control device, 26 is a power source, and 27 is an electric heater. As described above, according to the present invention, an insert having a spiral groove is inserted so as to come into close contact with the inner wall of the pipe, or an insert having a spiral groove on the inner wall is inserted into a pipe so as to come into close contact with the inner wall of the pipe. The decompression device is cooled from the outside with a low-temperature refrigerant, and the flow rate of the refrigerant is controlled by adjusting the amount of cooling, which makes it easy to manufacture and inexpensive, and also allows for a compact refrigeration device. be.

Brief explanation of the drawings Fig. 1 is a cycle diagram of a refrigeration system using a conventional pressure reducing device, Fig. 2 is a cross-sectional view showing the pressure reducing device, and Fig. 3 is a diagram showing the amount of refrigerant cooled when cooling the pressure reducing device. 4 is a block diagram showing an embodiment of the present invention, FIG. 5 is a sectional view of a pressure reducing device according to the present invention, and FIGS. 6 to 9 are other embodiments of the present invention. A diagram showing
FIG. 10 is a diagram showing the configuration of a conventional heat pump device, FIGS. 11 to 16 are diagrams showing the configuration of a heat pump device according to the present invention, and FIG. 17 and FIG. It is a figure showing an example.

In the figure, 1 is a compressor, 2 is a condenser, 4 is an evaporator, 5 is a flow rate adjustment valve, 6 is a valve lift control device, 7 is a heat exchange section, 8 is a vibrator, 9 is a heat insulator, 10 is a pressure reduction device, 11 is a heat exchange part, 12 is an insert, 13 is a groove, 14 is a cavity, 15 is 2
Heavy pipe part, 16 is a small hole, 17 is a vibrator, 18 is a through hole, 1
9 is a fin, 20 is a four-way switching valve, 21 is an indoor heat exchanger,
22 is an outdoor heat exchanger, 23 is a check valve, 24 is a flow rate adjustment device, 25 is an electric input control device, 26 is a power source, and 27 is an electric heater.

Claims (1)

[Claims] 1. A refrigeration system in which a compressor, a condenser, a pressure reducing device, and a condenser are sequentially connected in an annular manner, wherein the pressure reducing device includes an insert that forms a spiral groove between the inner wall surface of the pipe and The refrigerant flowing through the groove is cooled by an external low-temperature refrigerant, and the flow rate of the low-temperature refrigerant is controlled by using a refrigerant inserted closely into the inner wall of the pipe. refrigeration equipment. 2. Claim 1, characterized in that a small hole is provided at the outlet of the pressure reducing device, and a double pipe-shaped flow path is provided so as to surround the small hole, and a low-temperature refrigerant is introduced into the inside of the small hole. Refrigeration equipment. 3. The refrigeration system according to claim 1 or 2, characterized in that a through hole is formed inside the insert, and the low temperature refrigerant is introduced into the through hole from the pressure reducing device inlet side.