JPS5927162A - Refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a refrigeration system used in a two-temperature refrigerator or the like.

Conventional configuration and its problems Conventionally, as shown in FIG. Normally, refrigerant is supplied to the freezer compartment evaporator d via the refrigerator compartment evaporator C to cool them simultaneously, by means of a solenoid valve.
When the temperature of the refrigerator compartment falls below the set temperature, open the solenoid valve e.
The solenoid valve is closed to supply refrigerant only to the freezer compartment evaporator d. At this time, when the solenoid valve e is closed, the pressure inside the second cabinet IJf is under the pressure inside the freezer compartment evaporator d, and when the circuit is switched, that is, when the solenoid valve e is opened and the solenoid valve When closed, the liquid refrigerant flowing into the second capillary reach tube f rapidly evaporates, creating a gas choke, and as a result, the refrigerant in the system flows into the condenser q.
There was a problem that a so-called pump-down phenomenon occurred, resulting in poor cooling.

OBJECTS OF THE INVENTION An object of the present invention is to prevent the internal pressure of the second capillary reach tube from decreasing when no refrigerant is passed through the second capillary reach tube in order to prevent the generation of flash gas that occurs when a solenoid valve is switched.

Structure of the Invention In order to achieve this object, an on-off valve disposed on the side of the circuit bypassing the refrigerator compartment evaporator is provided on the downstream side of the second capillary reach tube, and while the on-off valve is closed, the second capillary reach tube is Prevents the internal pressure from falling below the pressure inside the freezer compartment evaporator.
When the electromagnetic valve is opened, the liquid refrigerant in the condenser is smoothly guided, preventing the generation of flash gas and eliminating the need for 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 Figure 1, 1 is a compressor, 2 is a condenser, 3 is a first capillary tube, 4 is a refrigerator compartment evaporator for cooling the inside of the refrigerator compartment, and 5 is a freezer compartment evaporator for cooling the freezer compartment. A first solenoid valve 7 is connected between the condenser 2 and the first capillary tube 3 to form a first refrigeration circuit 6. -1: da8 is second
This second capillary tube 8 is a capillary tube between the condenser 2 and the first on-off valve (hereinafter referred to as the first solenoid valve) and between the refrigerator compartment evaporator 4 and the freezer compartment evaporator 5. A second on-off valve 9 (hereinafter referred to as a second solenoid valve) is provided at the outlet of the second capillary.

That is, the compressor 1, the condenser 2, the second capillary tube 8,
The second solenoid valve 9 and the freezer compartment evaporator 5 constitute a second refrigeration circuit 1o. And the first refrigeration circuit 6
The second refrigeration circuit 1o is selectively operated by a first solenoid valve 7 provided between the condenser 2 and the first capillary 3 and a second solenoid valve 9 provided at the outlet of the second capillary 8. It is configured to switch to Note that normally the first solenoid valve 7 is open and the second solenoid valve is closed to form the first refrigeration circuit 6, and when the first solenoid valve is opened and the second solenoid valve 9 is opened, the second solenoid valve is closed. This switches to the refrigeration circuit 1o.

Next, the electric circuit shown in FIG. 2 will be explained.

When the temperature inside the movable contact 11a exceeds the set value, the movable contact 11a
The movable contact 11a is provided with a first fixed contact 11b that is closed, and a second fixed contact 11c that is closed when the indoor temperature falls below a set value.

A movable contact 11a of this refrigerator room thermostat 11 is connected to one end of an AC power source 13. The first fixed contact 11b of the refrigerator thermostat 11 is connected to the other end of the power source 13 via the excitation coil 14 of the first electromagnetic valve 7 constituting the first refrigeration circuit 6. Furthermore, the second fixed contact 11C of the refrigerator compartment thermostat 11 is connected to the second fixed contact 11C.
The excitation coil 1 of the second solenoid valve 9 constituting the refrigeration circuit 10 of
5 to the other end of the power source 13. A compressor drive motor 16 is connected to the power source 13 in series with a freezer thermostat 12 that detects the temperature of the freezer compartment. 12d is a movable contact, and 12b is a fixed contact.

The operation in such a configuration will be explained. First, during installation,
Alternatively, the evaporator 4 for the refrigerator compartment and the evaporator 5 for the freezer compartment are not cooled at all. In this state, the temperature inside the freezer and the temperature inside the refrigerator are above the set values, so the movable contact 12a of the freezer thermostat 12 is connected to the fixed contact 12.
Close to b. Therefore, the compressor drive motor 16 is driven and the compressor 1 starts operating.

Immediately after the compressor 1 starts operating, the temperature in the refrigerator compartment is higher than the set value, so the movable contact 11a of the refrigerator compartment thermostat 11 is closed to the first fixed contact 11b, and the excitation coil 14 of the first solenoid valve 7 is energized. A cooling operation is performed in the first refrigeration cycle 6, and the refrigerator compartment and the freezer compartment are respectively cooled.

When the temperature inside the refrigerator compartment falls below the set value, the movable contact 11a of the refrigerator compartment thermostat 11 separates from the first fixed contact 11b and closes to the second fixed contact 11C.
The excitation coil 15 of the second electromagnetic valve 9 is energized, a cooling operation is performed in the second refrigeration circuit 1o, and only the freezer compartment is cooled.

Note that the compressor 1 is turned on and off by a freezer compartment thermostat 12.

Therefore, when performing cooling operation in the first refrigeration circuit 6,
Since the pressure in the second refrigeration circuit 10 does not drop to the pressure in the freezer compartment evaporator 5, when the 2'1L magnetic valve 9 is opened, the liquid refrigerant in the second refrigeration circuit 1Q evaporates. It flows to the freezer compartment evaporator 5 without any waste.

The moving bed of the invention The present invention provides a moving bed for the second capillary tube in the second refrigeration circuit (a second capillary tube at the mouth part).
By installing an on-off valve, it is possible to prevent a pressure drop in the second refrigeration circuit when operating in the first refrigeration circuit, eliminating the pump-down phenomenon that would occur instantly when switching from the first refrigeration circuit to the second refrigeration circuit. and normal circulation can occur.

[Brief explanation of the drawing]

Fig. 1 is a refrigeration system diagram showing one embodiment of the present invention;
The figure is an electric circuit diagram in the same embodiment, and FIG. 3 is a refrigeration system diagram showing a conventional example. 1... Compressor, 2... Condenser, 3.
...First capillary tube, 4...Evaporator for refrigerator compartment, 5.
... Evaporator for freezer compartment, 6... First refrigeration circuit, 7... First on-off valve (first solenoid valve), 8...
...Second capillary tube, 9...Second on-off valve (second
solenoid valve), 10... second refrigeration circuit, 11...
Refrigerator thermostat, 52... Agent's name Patent attorney Toshio Nakao and one other person Hana 1 Figure 2 Figure 3

Claims (1)

[Claims] A first valve comprising a compressor controlled by a freezer thermostat, a first on-off valve controlled by a refrigerator thermostat, a first capillary, a refrigerator evaporator, and a freezer evaporator.
a second refrigeration circuit having a refrigeration circuit, a second capillary tube and a second on-off valve located downstream of the second capillary tube and controlled by a refrigerator room thermostat; and one end of the second refrigeration circuit connected to the condenser. The refrigeration system is connected between the first on-off valve and the second on-off valve at the other end is connected between the freezer compartment evaporator and the refrigerator compartment evaporator.