JPS6024909B2 - refrigeration cycle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigeration cycle configured to distribute liquid refrigerant to two coolers through respective capillary tubes, and its purpose is to stop the supply of liquid refrigerant to one cooler. To achieve this, it is an object of the present invention to provide a refrigeration cycle that can improve the heating efficiency of a heater that heats a capillary tube of the cooler.

An embodiment in which the present invention is applied to a refrigeration cycle of a refrigerator will be described below with reference to FIGS. 1 to 4.

First, in the refrigeration cycle shown in FIG. 1, numeral 1 is a compressor, and its discharge port 2 is connected to a main capillary tube 4 via a condenser 3. The outlet side end of this main capillary tube 4 is branched into two, one of which is connected to the inlet of a first cooler 6 for cooling the refrigerator compartment via a first cooler capillary tube 5, and the other branch is connected to the inlet of a first cooler 6 for cooling the refrigerator compartment. The end is connected to the inlet of the second cooler 8 for cooling the freezer compartment via the capillary tube 7 for the second cooler, and the common connection between the outlet of the first cooler 6 and the outlet of the second cooler 8 is connected. Inlet 1 of compressor 1 via suction pipe 9
01 is connected. Now, to explain the first condenser capillary tube 5 in detail, the second condenser capillary tube 5 will be described in detail.
In the figures and FIG. 3, the first cooler capillary tube 5 includes an inlet capillary tube 11 formed in the shape of a conical coil in which a heater to be described later is housed inside, and a pipe diameter of the inlet capillary tube 11. The inlet end of the inlet capillary tube 11 is connected to the one branch end of the main capillary tube 4, and the inlet end of the inlet capillary tube 11 is connected to the one branch end of the main capillary tube 4. The outlet end is connected to the inlet of the first cooler 6. Reference numeral 13 denotes a core tube made of, for example, aluminum and formed into a conical shape, and the inflow side capillary tube 11 is tightly wound around the outer periphery of this core tube 13. 14 is a heater, which has a conical heat-resistant core material 15 and a nichrome wire 16, for example.
This nichrome wire 16 is further molded with a heat-resistant insulating material.

By inserting the conical heater 14 into the core tube 13 of the inflow capillary tube 11, the heater 14 is brought into close contact with the inflow capillary tube 11. Next, in the electrical circuit diagram shown in Figure 4, 1
7 and 18 are power terminals connected to, for example, a 100V single-phase AC power source; 19 is a temperature control switch for the refrigerator compartment that turns on and off in response to the internal temperature of the refrigerator compartment; The temperature control switch for the freezer compartment is turned on and off by switching on and off, and connects both the series circuit between the temperature control switch 19 for the refrigerator compartment and the nichrome wire 16 of the heater 14, and the series circuit between the temperature control switch 20 for the freezer compartment and the compressor 1. Power terminal 1
7 and 18 are connected in parallel. Next, the operation of the above configuration will be explained.

First, when the compressor is operating, cold soot is compressed by the compressor 1 and liquefied by the condenser 3 from the main capillary tube 4 to the first cooler capillary tube 5.
It is distributed to the first and second coolers 6 and 8 via capillary tubes 7 for the second cooler in parallel, respectively, and cools the refrigerator compartment and the freezer compartment, respectively. When the temperature of the refrigerator compartment falls below a predetermined temperature, the temperature control switch 19 for the refrigerator compartment is turned on.
This causes the heater 4 to generate heat and heat the inflow side capillary tube 11 of the first cooling capillary tube 5. For this reason, the vapor pressure of the liquid-cooled soot flowing through the inflow-side capillary tube 11 increases, and the liquid-cooled soot further vaporizes under this high pressure, and the vaporized cold soot generated in this way in the inflow-side capillary tube 11 increases. It flows into the small-diameter outflow capillary tube 12 which has flow path resistance, and in the process of flowing through this, it receives the high flow path resistance and the pressure inside the outflow side capillary tube 12 increases. Therefore, the internal pressure of the first cooler capillary tube 11 further increases, and the supply of liquid-cooled soot to the first cooler 6 is stopped due to resistance based on this pressure. On the other hand, since the liquid refrigerant continues to flow into the second cooler 8, cooling of the freezer compartment continues, and when the freezer compartment is cooled to a predetermined temperature or less, the freezer compartment temperature control switch 20 is turned off. , the compressor stops operating.
By the way, if a heater is attached to almost the entire capillary tube for the first cooler, the vaporized cold butterfly generated by heating at the outflow side of the capillary tube for the first cooler will flow a short distance through the capillary tube for the first cooler. Since it flows out without much resistance, it does not contribute much to the increase in the internal pressure of the first cooler capillary tube.
For this reason, the heat generated by the heater cannot be used effectively, resulting in wasted power.

However, according to this embodiment, since the heater 14 is attached only to the inflow side capillary tube 11 of the first cooler capillary tube 5, all of the vaporized cold butter heated and generated by the heater 14 has a flow path resistance. passes through the large outflow side capillary tube 12 and effectively contributes to increasing the internal pressure of the first cooler capillary tube 5.

Therefore, the heat generated by the heater 14 can be used effectively, and the power consumption of the heater 14 can be kept low. In order to further reduce the power consumption of the heater, it is possible to reduce the diameter of the entire capillary tube for the first cooler to increase its flow resistance. Due to the increase in flow path resistance of the capillary tube, even when liquid refrigerant should be supplied to the first cooler, it becomes difficult for the liquid refrigerant to flow into the first cooler, resulting in the problem that the first cooler is not cooled properly. In order to deal with this problem, the diameter of the capillary tube for the second condenser is also made smaller. This increases the pressure at the branch end of the main capillary tube, which increases the heating temperature of the capillary tube for the first condenser (steam If the pressure is not increased (increased pressure), the supply of liquid-cooled soot to the first cooler cannot be stopped, and as a result, a heater with a high calorific value must be used.

However, according to this embodiment, since the flow path resistance of the outflow side capillary tube 12 of the first cooler capillary tube 5 is made larger than the flow path resistance of the inflow side capillary tube 11, The flow path resistance of the first cooler capillary tube 5 as a whole can be kept low while ensuring a sufficient flow path resistance in the portion that contributes most to the increase in internal pressure of the capillary tube 5 (the outflow side capillary tube 12). .

Therefore, when the heater 14 is cut off, the flowability of the liquid cooled soot in the first cooler capillary tube 5 can be maintained well, and the required amount of liquid refrigerant can be supplied to the first cooler 6. Moreover,
By keeping the flow path resistance of the first cooler capillary tube 5 low, the flow path resistance of the second cooler capillary tube 7 can also be kept low, so it is possible to suppress the pressure rise at the branch end of the main capillary tube 4. . Therefore, it is not necessary to excessively increase the pressure inside the first cooler capillary tube 5 when the heater 14 is energized, and the amount of heat generated by the heater 14 and hence the power consumption can be reduced accordingly. Furthermore, in the case where the cooling fluid flowing through the first cooler capillary tube 5 is heated by the heater 4 and vaporized during the cooling operation as described above, according to this embodiment, the inflow side formed in a conical coil shape is used. Since the conical heaters 14 are closely arranged inside the capillary tube 11, the adhesion of the heaters 14 to the inflow capillary tube 11 is improved, and in particular, as in this embodiment, the heater 16 is closely arranged in the inflow capillary tube. If the heater 4 is disposed inside the tube 11, the heat of the heater 4 is dissipated to the outside, and as a result, the heat conductivity of the heater 14 to the inflow side capillary tube 11, and hence the heating efficiency can be improved. As explained above, the main feature of the present invention is that the flow path resistance of the part of the capillary tube for the first cooler that is closer to the first cooler than the part heated by the heater is made larger than that of the part heated by the heater. As a result, even if the heater generates a low amount of heat, it is possible to reliably supply and stop the medium to the first cooler by energizing the heater, thereby reducing power consumption. In addition, it is possible to provide a refrigeration cycle in which a required amount of liquid-cooled soot can flow into the first cooler when the heater is turned off.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a refrigeration cycle configuration diagram, FIG. 2 is an exploded longitudinal sectional view of the main parts, FIG. 3 is a longitudinal sectional view of the main parts, and FIG. 4 is an electric circuit diagram. It is. In the drawing, 5 is a capillary tube for a first cooler, 6 is a first cooler, 7 is a capillary tube for a second cooler, 8 is a second cooler, and 14 is a heater. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. The refrigerant is distributed to the first cooler and the second cooler through the first cooler capillary tube and the second cooler capillary tube, respectively, and the refrigerant is supplied to the first cooler through the first cooler capillary tube. In a tube that is controlled by turning on and off a heater that heats the tube, the flow path resistance of a portion of the first cooler capillary tube that is closer to the first cooler than the part heated by the heater. A refrigeration cycle characterized in that the flow path resistance is greater than the flow path resistance of the portion heated by the heater.