JPH0526437Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) The present invention includes a first cooler provided in a storage chamber and a second cooler that cools the inside of the storage chamber. related to the refrigeration cycle.

(Prior Art) This type of refrigeration cycle in a conventional refrigerator is shown in FIG. In the figure, 1 is a compressor, 2 is a condenser, 3 is a first expansion device, 4 is a direct cooling cooler that directly cools the freezer compartment, 5 is a second expansion device,
Reference numeral 6 denotes a cooler for cooling the freezer compartment and the refrigerator compartment by forced circulation of cold air by a fan 7.

The direct cooling cooler 4 provided in the freezer compartment is used particularly when food is placed therein and the food is rapidly cooled. For this reason, if frost forms on this direct cooling cooler 4, the rapid cooling efficiency for food will decrease, so it is necessary to prevent frost from accumulating as much as possible. A second throttle device 5 is provided for this purpose, and this second throttle device 5
is present between both the direct cooling and intercooling coolers 4 and 6, so that the evaporation temperature in the intercooling cooler 6 is lower by a predetermined temperature than that in the direct cooling cooler 4 during operation of the compressor 1. Become. Therefore, if frost forms on the direct cooling cooler 4 on the high temperature side, the frost will sublimate and transfer to the intercooling cooler 6 on the low temperature side. This means that there will be almost no frost.

(Problem to be solved by the invention) However, in the refrigeration cycle with the above configuration, when food is placed on the direct cooling cooler 4 and the food is rapidly cooled, the refrigerant is not used in the direct cooling cooler 4. evaporates actively and performs a cooling effect, so the refrigerant passing through the second expansion device 5 has an increased ratio of gas refrigerant compared to liquid refrigerant (that is, the dryness is increased), and the refrigerant passes through the second expansion device 5.
The flow path resistance within the throttling device 5 increases substantially.
As a result, the temperature of the direct cooling cooler 4 becomes higher than the temperature of the intercooling cooler 6 during normal cooling operation, resulting in a problem that the time required for rapid cooling becomes longer. . In particular, in recent refrigerators, the rotation speed of the compressor motor is switched by frequency control of the inverter, and during rapid cooling operation, the rotation speed of the compressor motor is increased to increase the amount of refrigerant circulation, resulting in rapid cooling. Although attempts have been made to make the effect even higher, there is also a problem in this case in that the rapid cooling time is not shortened as much as expected.

The present invention was made in view of the above circumstances, and its purpose is to prevent frost from accumulating on the first cooler installed in the storage room, and to prevent frost from accumulating on the first cooler during rapid cooling operation. The purpose of the present invention is to provide a refrigeration cycle that can maintain the temperature at a lower temperature and has a high rapid cooling effect.

[Effects of the invention] (Means for solving the problem) The refrigeration cycle of the invention includes a condenser, a first throttling device, and a storage chamber arranged between the discharge side and the suction side of the compressor. Cooled air placed in a first cooler, a second throttle device, and a portion communicating with the storage chamber is blown into the storage chamber by a fan. Second coolers are connected in series in order, and the second cooler is connected between the inlet side of the first cooler and the connection part of the second throttle device and the second cooler.
This device is characterized by connecting a bypass path with a flow resistance greater than that of the throttling device.

(Function) When food is placed on the first cooler, the amount of evaporation of the refrigerant in the first cooler increases, and as a result, it flows into the second cooler through the second throttle device. The amount of liquid refrigerant decreases. Therefore, the resistance value of the second throttle device substantially increases, and liquid refrigerant proportional to the substantially increased resistance value of the second throttle device and the resistance value of the bypass path passes through the bypass path. Then, it flows into the second cooler and is evaporated in the second cooler. As a result, the relative pressure difference between the second cooler and the first cooler decreases, and the evaporation pressure and therefore the evaporation temperature of the refrigerant in the first cooler decreases accordingly.

(Example) An example of the present invention will be described below with reference to FIG. Reference numeral 11 denotes a rotary type compressor, for example, whose drive source is a variable speed motor whose frequency is controlled by an inverter. A condenser 12, which serves as a first throttling device, is connected between the discharge port 11a and the suction port 11b of the compressor 11. A first capillary reach tube 13, a direct cooling cooler 14 which is a first cooler provided in the form of a shelf in a freezing chamber which is a storage room (not shown), a second capillary reach tube 15 which is a second expansion device, and the above. A cooler room is provided that communicates with a freezer compartment and a refrigerator compartment (not shown) via an air passage, and both the freezer compartment and refrigerator compartment (not shown) are cooled by forced circulation of cold air by a fan 16 that rotates in synchronization with the operation of the compressor 11. A second cooler 17 is connected in series in order. 18 is the inlet side of the direct cooling cooler 14, the second capillary reach tube 15, and the intercooling cooler 17
This bypass path is connected between the connecting portion of the capillary reach tube 15 and the flow path resistance thereof is set to be approximately two to five times the flow path resistance of the second capillary reach tube 15.

Next, the operation of the above configuration will be explained. First of all,
During normal cooling operation, the fan 16 rotates as the compressor 11 starts operating. The refrigerant compressed by the compressor 11 and condensed by the condenser 12 flows into the direct cooling cooler 14 via the first capillary reach tube 13, where the refrigerant evaporates and exhibits a cooling effect. Intercooler 17 through second capillary reach tube 15
flows into. In this case, the direct cooling cooler 14 includes:
Since there is no relatively high-temperature food to be cooled on the table, the heat load thereon is small. Therefore, the amount of refrigerant that evaporates in the direct cooling cooler 14 is small, and the refrigerant flowing in the second capillary reach tube 15 contains more liquid refrigerant and less gas refrigerant (that is, the degree of dryness is small), so the second Since the flow path resistance of the capillary reach tube 15 is smaller than the flow path resistance of the bypass path 18, most of the refrigerant flows through the direct cooling cooler 14 and the second capillary reach tube 15.
The water then flows into the intercooler 17 through the . Then, the liquid refrigerant that has flowed into the intercooling cooler 17 evaporates here, and the air in the freezer compartment and refrigerator compartment (not shown) is cooled by the intercooling cooler 17 due to the rotation of the fan 16. This circulation of cold air cools the freezer and refrigerator compartments. In this case, the direct cooling cooler 14 has a slightly higher temperature (about 5° C.) than the intercooling cooler 17 due to the presence of the second capillary reach tube 15, thereby preventing frost formation.

Now, when the rapid cooling operation in which the food placed on the direct cooling cooler 14 is rapidly cooled is selected,
The power frequency applied to the compressor motor is approximately 90Hz, which is higher than during normal cooling operation.
A larger amount of refrigerant is circulated through the refrigeration cycle than during normal cooling operation. In this rapid cooling operation, the refrigerant condensed in the condenser 12 flows into the direct cooling cooler 14 via the first capillary reach tube 13, as in the normal cooling operation described above. By the way, in the case of this rapid cooling operation, since the direct cooling cooler 14 is loaded with relatively high temperature food to be cooled, the thermal load on the direct cooling cooler 14 is increased. big. Therefore, the liquid refrigerant actively evaporates in this direct cooling cooler 14, and the refrigerant passing through the second capillary reach tube 15 contains more gas refrigerant than liquid refrigerant (i.e. due to increased dryness),
The liquid refrigerant becomes difficult to flow through the second capillary reach tube 15. Then, the amount of liquid refrigerant that flows into the bypass path 18 on the inlet side of the direct cooling cooler 14 increases, and the liquid refrigerant that flows through this bypass path 18 and flows into the intercooling cooler 17 is used for intercooling. Cooler 1
7 becomes extremely low in a short period of time. As described above, the temperature of the intercooling cooler 17 becomes extremely low, and the relative pressure difference between the intercooling cooler 17 and the direct cooling cooler 14 decreases, so the direct cooling cooler 17 1
The evaporation pressure and therefore the evaporation temperature of the liquid refrigerant in step 4 are lowered, and the food placed on the direct cooling cooler 14 can be rapidly cooled. In the case of this rapid cooling operation, in this embodiment, the rotation speed of the compressor motor is higher than that during normal cooling operation, so the evaporation pressure (evaporation temperatures) are lower and food can be cooled more quickly.

[Effect of the invention] As is clear from the above explanation, the present invention has the first effect.
A cooler is disposed inside the storage chamber, a second cooler is disposed at a portion communicating with the storage chamber, and an air fan cooled by the second cooler is configured to blow air into the storage chamber. At the same time, it should be noted that a bypass passage having a flow resistance greater than that of the second throttle device is connected between the inlet side of the first cooler and the connection part of the second throttle device and the second cooler. This feature allows the liquid refrigerant to be supplied to the second cooler through the bypass path during rapid cooling to lower the temperature of the second cooler. The temperature of the cooler will also be lower. Therefore, due to the presence of the second throttling device, the first cooler is kept at a slightly higher temperature than the second cooler to prevent frost build-up, and the food can be more effectively and rapidly processed. Can be cooled. Moreover, the control for supplying the liquid refrigerant to the second cooler without passing through the first cooler during rapid cooling as described above can be performed simply by providing a bypass path without using a solenoid valve or the like. Since it can be realized, it is possible to obtain excellent effects such as being advantageous in terms of cost.

[Brief explanation of drawings]

Figure 1 is a refrigerant cycle diagram of the present invention;
The figure is a diagram corresponding to FIG. 1 showing a conventional example. In the figure, 11 is a compressor, 12 is a condenser, 13 is a first capillary reach tube (first restrictor), 14 is a direct cooling cooler, and 15 is a second capillary reach tube (first restrictor). , 17 is an intercooler, and 18 is a bypass path.

Claims (1)

[Scope of utility model registration request] A condenser, a first throttling device, a first cooler disposed inside the storage chamber, a second throttling device, and a portion communicating with the storage chamber are arranged between the discharge side and the suction side of the compressor. A second cooler that blows cooled air into the storage chamber by a fan is connected in series, and a connection part between the inlet side of the first cooler, the second throttle device, and the second cooler. A refrigeration cycle characterized in that a bypass path having a flow resistance greater than that of the second throttling device is connected between the refrigeration cycle and the second throttling device.