JPS6240631B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a refrigerant amount adjusting device that can change the amount of refrigerant circulating in a refrigerant circuit in response to a change in load, and can exhibit the maximum refrigerating capacity according to the load. It is something.

Conventionally, a refrigeration system equipped with a refrigerant amount adjustment device connects a compressor a, a condenser b, a throttle device c, and an evaporator d in a ring, and throttles a refrigerant amount adjustment container e, as shown in Fig. 1. Connected to a connection position g in the middle of the device c or between the throttle device c and the evaporator d,
Furthermore, the suction pipe f penetrated into the refrigerant amount adjustment container e.

In such a configuration, the refrigerant at the connection position g between the throttle device c and the refrigerant amount adjustment container e is in a gas-liquid two-phase saturated state, so if the suction pipe f penetrates the refrigerant amount adjustment container e, If not, the refrigerant state inside the refrigerant amount adjustment container e will be in the same saturated state as the refrigerant at the connection position g between the expansion device c and the refrigerant amount adjustment container e. However, when the suction pipe f passes through the refrigerant amount adjustment container e, the temperature of the suction pipe f is usually lower than the temperature at the connection position g between the throttle device c and the refrigerant amount adjustment container e, so that the refrigerant A portion of the refrigerant inside the volume control container e condenses. Therefore, the wetness of the refrigerant inside the refrigerant amount adjusting container e is greater than the wetness of the refrigerant at the connection position g between the expansion device c and the refrigerant amount adjusting container e. In other words, the temperature of the suction pipe f is
When the temperature is lower than the temperature at the connection position g, the refrigerant is simply accumulated in the refrigerant amount adjustment container e. Furthermore, when the heat load is not extremely large, the temperature of the suction pipe f is lower than the temperature of the connection position g, and the temperature difference between the two is large. The refrigerant is in a supercooled liquid state, and even if there is a load change, the degree of supercooling of the refrigerant inside the refrigerant amount adjustment container e changes, and the inside of the refrigerant amount adjustment container e is almost liquid refrigerant. It will be occupied. In other words, the conventional refrigerant amount adjusting device has the disadvantage that it hardly performs the function of adjusting the amount of refrigerant in response to normal load fluctuations, and that liquid returns to the compressor especially at low loads.

Therefore, the present invention solves the above-mentioned conventional drawbacks and changes the amount of refrigerant flowing through the refrigerant circuit even in response to normal load fluctuations, thereby making it possible for the refrigeration system to always demonstrate its maximum capacity in accordance with the load. It made it possible.

Hereinafter, one embodiment of the present invention will be explained with reference to FIGS. 2 and 3. As shown in FIG. 2, a compressor 1, a condenser 2, a throttle device 3, and an evaporator 4 are connected in a ring. The refrigerant amount adjustment container 5 is connected to a connection position 3a in the middle of the expansion device 3. Further, the suction pipe 6 connects the compressor 1 and the evaporator 4, and one end of the branch pipe 7a is connected to a branch point 7b in the middle of the connecting pipe 7 that connects the condenser 2 and the throttling device 3. The other end of the branch pipe 7a is connected to a confluence point 7c located midway along the connection pipe 7 and closer to the throttle device 3 than the branch point 7b. moreover,
As shown in FIG. 3, the suction pipe 6 and the branch pipe 7a
and are respectively disposed in the refrigerant amount regulating container 5 in a heat exchange manner.

Next, the operation of the above-mentioned refrigerant amount adjusting device will be explained.

Generally, the temperature of the suction pipe 6 changes sensitively and greatly with respect to load fluctuations, but the temperature of the connection position 3a between the refrigerant amount adjustment container 5 and the expansion device 3 does not change much.

Now, assume that the refrigerant is filled with the necessary refrigerant so that the refrigeration system exhibits its maximum capacity under certain design heat load conditions. When the refrigeration system is operated under a certain load condition, the temperature of the suction pipe 6 is also maintained at a certain temperature. At this time,
The temperature of the suction pipe 6 passing through the refrigerant amount adjustment container 5 is lower than the temperature at the connection position 3a between the refrigerant amount adjustment container 5 and the expansion device 3, and the temperature of the branch pipe 7a is lower than the temperature at the connection position 3a. higher than the temperature. Therefore, the temperature of the refrigerant inside the refrigerant amount adjustment container 5 shows a saturation temperature equal to the temperature of the refrigerant at the connection position 3a between the refrigerant amount adjustment container 5 and the expansion device 3, but the refrigerant inside the refrigerant amount adjustment container 5 humidity and the connection position 3a
The wetness of the refrigerant will be different. When adjusting the amount of refrigerant, it is important to adjust the wetness of the refrigerant inside the refrigerant amount adjustment container 5. In other words, since there is a large difference in specific weight between the gas state and the liquid state of the refrigerant,
It is important to control the ratio of the liquid phase of the refrigerant inside the refrigerant amount adjustment container 5.

In FIG. 4, the diameter of the branch pipe 7a is plotted on the horizontal axis, and the humidity of the refrigerant inside the refrigerant amount regulating container is plotted on the vertical axis, and the refrigerant amount regulating container 5 under a certain design heat load condition is shown. This shows the proportion of the liquid phase of the refrigerant inside. For example, in FIG. 4, if a branch pipe 7a having a pipe diameter indicated by point h is used, the wetness of the refrigerant inside the refrigerant amount adjustment container will be i under the design load conditions. As explained above, the humidity of the refrigerant inside the refrigerant amount adjustment container can be set to any desired humidity by appropriately selecting the pipe diameter of the branch pipe 7a. As shown in FIG. 5, the wetness of the refrigerant inside the refrigerant amount regulating container can be appropriately selected by providing fins 8 on the suction pipe 6 and the branch pipe 7a and changing the heat transfer area of the fins.

Next, the operation of the refrigerant amount adjusting device when the load fluctuates will be explained. First, considering the case where the load decreases, an excess amount of refrigerant will be circulating in the refrigerant circuit than the amount of refrigerant that allows the refrigeration system to exhibit its maximum capacity under this load condition, so refrigerant with almost no superheat or The refrigerant, which remains partially liquid, is sucked into the compressor 1 through the suction pipe 6,
The temperature of the suction pipe 6 becomes lower than before the load is reduced. Furthermore, if the load decreases, the temperature of the refrigerant after passing through the condenser 2 generally decreases, so the temperature of the branch pipe 7a also decreases. in this way,
When the load decreases, the temperatures of both the suction pipe 6 and the branch pipe 7a passing through the refrigerant amount adjustment container decrease. Therefore, the refrigerant in a saturated vapor state inside the refrigerant amount adjustment container 5 condenses, so that the wetness of the refrigerant inside the refrigerant amount adjustment container 5 increases, and the proportion of the liquid phase of the refrigerant increases. As a result, the mass of the refrigerant contained inside the refrigerant amount adjustment container 5 increases compared to before the load change. This increased refrigerant is
After all, the refrigerant in the refrigerant circuit is the refrigerant that has flowed into the refrigerant amount adjustment container 5 from the connection position 3a in the middle of the expansion device 3, so the excess refrigerant in the refrigerant circuit has been removed, and the suction pipe The temperature at 6 increases to balance the temperature at the connection location 3a.

Next, the action of the refrigerant amount adjustment container when the load increases will be explained. When the load increases, the amount of refrigerant circulating in the refrigerant circuit becomes insufficient than the amount of refrigerant that allows the refrigeration system to exhibit its maximum capacity under this load condition.
It will be sucked into the compressor 1 through.
In other words, the temperature of the suction pipe 6 becomes higher than before the load change. Additionally, as the load increases, the temperature of the refrigerant after passing through the condenser 2 generally increases, so
The temperature of the branch pipe 7a also increases. In this way, if the load increases, the temperatures of both the suction pipe 6 and the branch pipe 7a, which pass through the refrigerant amount adjustment container, increase. For this reason, the refrigerant in a saturated liquid state inside the refrigerant amount adjustment container 5 evaporates, so the wetness of the refrigerant inside the refrigerant amount adjustment container 5 decreases, and the proportion of the liquid phase of the refrigerant decreases.

As a result, the mass of the refrigerant contained inside the refrigerant amount adjustment container decreases compared to before the load change. This decreased refrigerant is the refrigerant that has flowed into the refrigerant circuit from the connection position 3a in the middle of the expansion device 3, and the refrigerant inside the refrigerant amount adjustment container 5 has flowed into the refrigerant circuit, which was in short supply. As the refrigerant is replenished, the temperature of the suction pipe 6 decreases and becomes balanced with the temperature of the connecting position 3a in the middle of the expansion device 3.

Next, FIG. 6 shows another embodiment of the refrigerant amount adjusting device according to the present invention. The difference between FIG. 2 and FIG. 6 described above is that in FIG.
It is characterized by passing through the refrigerant amount adjustment container 5, and in FIG. 6, it is characterized by passing through the refrigerant amount adjustment container 5 without branching the connecting pipe 7 that connects the condenser 2 and the expansion device 3. This is the point.

The refrigerant amount adjusting device shown in FIG. 6 also provides the same effects as the previous embodiment. Here, the same parts as in FIG. 2 are given the same numbers, and the description thereof will be omitted.

In the examples shown in FIGS. 2, 3, 5, and 6, a connecting pipe 7 connecting the condenser 2 and the throttle device 3, or a branch pipe branching from the connecting pipe 7 7a and the suction pipe 6 into the refrigerant amount adjustment container 5.
The purpose of this passage is to allow the connecting pipe 7 or the branch pipe 7a and the suction pipe 6 to exchange heat with the refrigerant amount adjusting container 5, respectively. Therefore, the connecting pipe 7 or the branch pipe 7a and the suction pipe 6 may be placed in contact with the refrigerant amount adjusting container 5 to exchange heat.

As described above, the refrigerant amount adjustment device in a refrigeration system of the present invention is a refrigeration system in which a compressor, a condenser, a throttle device, and an evaporator are each connected in a ring shape.
Place the refrigerant amount adjustment container in the connecting position in the middle of the throttling device.
Alternatively, a connecting pipe connected between the throttle device and the evaporator and further connects the condenser and the throttle device;
Alternatively, a branch pipe branched from the connecting pipe and a suction pipe are arranged in the refrigerant amount adjustment container for heat exchange, so that the refrigerant amount can be adjusted over a wider range of load fluctuations than conventional refrigerant amount adjustment devices. It is possible to adjust the
Furthermore, unlike conventional refrigerant amount adjustment devices, a connecting pipe connecting the condenser and the expansion device, or a branch pipe formed by branching a part of the connecting pipe, is arranged in the refrigerant amount adjusting container for heat exchange. Therefore, by appropriately selecting the pipe diameter of the connecting pipe or the pipe diameter of the branch pipe, it is possible to arbitrarily select the amount of refrigerant that can be stored in the refrigerant amount adjustment container under the design load conditions.
The size of the refrigerant amount adjustment container can be easily determined so that the refrigerant amount adjustment function can be adequately performed for the maximum and minimum load conditions considered at the time of design.
In addition, it is possible to fully adjust the amount of refrigerant at low loads, completely preventing liquid from returning to the compressor.
It has great effects.

[Brief explanation of the drawing]

FIG. 1 is a diagram of a refrigeration cycle equipped with a conventional refrigerant amount adjustment device, FIG. 2 is a diagram of a refrigeration cycle equipped with a refrigerant amount adjustment device according to an embodiment of the present invention, and FIG. 3 is a diagram of a refrigerant amount adjustment container. 4 is an explanatory diagram showing the wetness of the refrigerant in the refrigerant amount adjustment container,
FIG. 5 is a sectional view showing another example of the refrigerant amount adjustment container;
FIG. 6 is a refrigeration cycle diagram in another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Compressor, 2... Condenser, 3... Throttle device, 3a... Connection position, 4... Evaporator, 5... Refrigerant amount adjustment container, 6... Suction pipe, 7... Connection pipe, 7
a... Branch pipe.

Claims (1)

[Claims] 1 Compressor 1, condenser 2, throttle device 3, evaporator 4
In the refrigeration system, the refrigerant amount adjusting container 5 is connected to a position between the expansion device 3 and the evaporator 4 where the pressure is lower than the pressure on the inlet side of the expansion device 3, and the condenser A refrigerant amount adjusting device for a refrigeration system, in which a connecting pipe 7 and a suction pipe 6 connecting the refrigerant amount adjusting container 5 and the expansion device 3 are disposed in a heat exchange manner in the refrigerant amount adjusting container 5.