JPH0136034B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a refrigeration device such as a two-temperature refrigerator equipped with an evaporator for a freezer compartment and an evaporator for a refrigerator compartment.

Conventional structure and its problems As shown in FIG. 1, a conventional general refrigerant circuit related to the present invention supplies refrigerant by a compressor a through a condenser b, a capillary tube c, a freezer compartment evaporator d, The compressor a is supplied to the refrigerator compartment evaporator e and cooled at the same time, and the temperature inside the refrigerator is controlled by controlling the compressor a on and off using a thermostat (not shown) provided in the refrigerator compartment. Here f is a check valve,
This is to prevent the high temperature and high pressure gas in the compressor a from flowing back into the evaporator d for the freezer compartment and the evaporator e for the refrigerator compartment when the compressor a is stopped. is placed between. i is a solenoid valve for cutting off high-temperature, high-pressure gas; it opens only when compressor a is in operation, and prevents high-temperature refrigerant in condenser b from flowing to both evaporators d and e when compressor a is stopped. .

In such devices, defrosting of the refrigerator compartment evaporator e is generally performed every cycle when the compressor a is stopped, and conventionally, the defrosting of the refrigerator compartment evaporator e is performed in the vicinity of the refrigerator compartment evaporator e. When the compressor a was stopped, the heater h was turned on to defrost the compressor every cycle.

However, in the current environment where the energy saving trend is increasing, the power consumption by this heater cannot be ignored.

Purpose of the Invention The purpose of the present invention is to reduce the power consumption of the defrosting heater when the compressor is stopped, which is a drawback of the conventional example, by using the evaporator for the refrigerator compartment without having a thermal effect on the evaporator for the freezer compartment. The purpose is to defrost the container.

Structure of the Invention In order to achieve this object, a pressure on/off valve is installed between the evaporator for the freezer compartment and the evaporator for the refrigerator compartment, and when the compressor is stopped, the high-temperature, high-pressure refrigerant in the compressor is transferred to the evaporator for the refrigerator compartment. defrosting is performed by the amount of heat released when the refrigerant is condensed in the refrigerator compartment evaporator, and the defrosting heater of the refrigerator compartment evaporator is eliminated;
This is to avoid placing a heat load on the evaporator for the freezer compartment.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 2, 1 is a rotary compressor (high-pressure type inside the outer shell), 2 is a condenser, 3 is a capillary tube, 4 is an evaporator for the freezer compartment, and 5 is a high-temperature, high-pressure refrigerant in the rotary compressor 1 that is frozen. This is a pressure opening/closing valve that prevents backflow into the room evaporator 4, and is installed between the freezer compartment evaporator 4 and the refrigerator compartment evaporator 6.

As shown in FIG. 3, this pressure on/off valve 5 has an inlet pipe 5a connected to the outlet of the evaporator 4 for the freezer compartment, and an outlet pipe 5b connected to the inlet and outlet of the evaporator 6 for the refrigerator compartment.
have. 5c is the valve seat, 5d is the rod connected to the diaphragm 5e, and 5f is the rod 5.
The ball valve provided at the tip of e, 5g is a bias spring, and the anti-ball valve 5 of the diaphragm 5e
One end of a conduit 7 is connected to the pressure equalizing chamber 5h on the f side, and the other end is connected to the suction line 1a. When the pressure in the suction line 1a decreases due to the operation of the compressor 1, the pressure in the pressure equalizing chamber 5h decreases through the conduit 7, and this causes the ball valve 5
f is separated from the valve seat 5c, resulting in an open circuit state. Furthermore, when the compressor 1 stops and the pressure in the suction line 1a increases, the pressure equalizing chamber 5 is
The pressure within h increases, and as a result, the ball valve 5f is brought into close contact with the valve seat 5c, resulting in a closed circuit state.

Reference numeral 8 denotes a solenoid valve disposed on the outlet side of the condenser 2, which is opened when the compressor 1 is in operation and closed when the compressor 1 is stopped.

The operation in such a configuration will be explained. The temperature inside the refrigerator is controlled by a thermostat installed in the refrigerator compartment, and the temperature in the refrigerator compartment is detected by a thermostat temperature sensing part (not shown) installed on the surface of the refrigerator compartment evaporator 6. Compressor 1
ON/OFF controlled.

When the thermostat is ON, the refrigerant is supplied by the rotary compressor 1 to the evaporator 4 for the freezer compartment via the condenser 2 and capillary tube 3, and then to the evaporator 6 for the refrigerator compartment via the pressure shut-off valve 5. It is supplied to cool the freezer compartment and refrigerator compartment (none of which are shown).

When the temperature sensing part of the thermostat becomes lower than the set temperature, the thermostat is turned off and the rotary compressor 1 is stopped. When the rotary compressor 1 stops,
Due to its basic structure, the airtightness of the high and low pressures maintained during operation is broken, and the high-temperature, high-pressure refrigerant inside the outer shell flows back through the low-pressure side, that is, inside the suction pipe 1a, as shown by the broken line arrow in Figure 2, causing refrigeration. This will flow back into the indoor evaporator 6. The high-temperature, high-pressure refrigerant that flows backward is sequentially condensed in the refrigerator compartment evaporator 6, and the heat released at this time is used to defrost. At this time, the pressure opening/closing valve 5 closes the ball valve 5f due to the pressure increase in the pressure equalizing chamber 5h, and prevents the high-temperature, high-pressure refrigerant from flowing back into the freezer compartment evaporator 4, which may increase the freezer compartment temperature. There isn't. When defrosting using the high-temperature, high-pressure refrigerant progresses and the surface temperature of the refrigerator compartment evaporator 6 reaches the set temperature (0°C or higher), the thermostat is turned on again, and the defrosting is completed and the rotary compressor 1 starts cooling operation. At the same time, the pressure in the conduit 7 of the pressure opening/closing valve 5 becomes lower than the set pressure, and the valve 5 opens and sequentially forms a normal refrigerant circulation circuit.

As is clear from the above explanation, in this embodiment, the high-temperature, high-pressure refrigerant in the rotary compressor 1 is guided into the refrigerator compartment evaporator 6 for defrosting every cycle when the compressor is stopped. be.

In addition, under low outside temperatures, the high-temperature, high-pressure backflow refrigerant becomes an appropriate load, prevents the compressor operating rate from dropping drastically, and prevents the freezer compartment temperature from rising, which is consistent with reality. This is what I did.

Effects of the Invention The present invention installs a pressure on-off valve between the evaporator for the freezer compartment and the evaporator for the refrigerator compartment, and supplies the high-temperature, high-pressure refrigerant of the high-pressure compressor in the shell to the refrigerator compartment when the compressor is stopped. Since the defrost is carried out by introducing the defrost into the evaporator, there is no need for a defrost heater as in the past, or only a small amount of capacity is required, which has a significant energy saving effect.

[Brief explanation of drawings]

Figure 1 is a refrigerant circuit diagram of a conventional refrigeration system;
The figure is a refrigerant circuit diagram showing one embodiment of the refrigeration system of the present invention, and FIG. 3 is a sectional view of a pressure on-off valve. 1... Rotary compressor, 2... Condenser, 3... Capillary tube, 4... Evaporator for freezer compartment, 5... Pressure on/off valve, 6... Evaporator for refrigerator compartment, 7... Pressure on/off valve conduit, 1a...suction line.

Claims (1)

[Claims] 1. A high-pressure rotary compressor in the outer shell, a condenser, a capillary tube, an evaporator for the freezer compartment, an evaporator suction line for the refrigerator compartment, etc. are connected in sequence, and the evaporator for the freezer compartment and the evaporator for the refrigerator compartment are connected in sequence. A refrigeration system having a pressure on/off valve that closes in response to pressure fluctuations in the suction line that occur when the rotary compressor is stopped.