JPH11132577A - Refrigerating cycle of refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To start the refrigerating cycle of a refrigerator without requiring a high torque while eliminating pressure difference between the inlet and outlet thereof even when a compressor is stopped. SOLUTION: A compressor 12 a condenser 16, a capillary tube 24 and an evaporator 26 are coupled sequentially and a three-way valve is provided between the condenser 16 and the capillary tube 24. Furthermore, a refrigerant bypass pipe 30 is provided between one outlet of the three-way valve and the compressor 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating cycle in a refrigerator.

[0002]

2. Description of the Related Art Conventionally, various refrigerating cycles for refrigerators have been considered, but each has its own problems. Hereinafter, the configuration of a conventional example of the refrigeration cycle will be described, and problems will be described.

(First Conventional Example) FIG. 9 shows a refrigerant flow path of a refrigeration cycle 300 of a refrigerator of a first conventional example, and FIG. 10 shows a change in pressure of each part in the refrigeration cycle 300 during operation.

[0004] As shown in FIG.
The compressor 302 includes a condenser 304, a dew-proof pipe 306, a dryer 308, and a capillary tube 310.
And the evaporator 312 are connected in order.

During the operation of the refrigeration cycle 300, the pressure becomes high, and the refrigerant passes through the capillary tube 310, and becomes low pressure. On the other hand, when the temperature inside the refrigerator is cooled to a predetermined temperature and the compressor 302 stops, the refrigerant on the high pressure side such as the condenser 304 and the dew-proof pipe 306 passes through the capillary tube 310 and the evaporator 31
2, and the pressures on the high pressure side and the low pressure side are balanced.
At this time, the refrigerant does not flow from the high pressure side to the low pressure side after passing through the compressor 302.

However, when the refrigeration cycle 300 is stopped, the refrigerant on the high-pressure side flows into the evaporator 312, so that the temperature of the evaporator 312 rises and the temperature inside the refrigerator also rises, so that a loss occurs in the refrigeration cycle of the refrigerator. There was a problem.

(Second Conventional Example) In order to prevent the loss of the refrigeration cycle 300 in the first conventional example, there is a refrigeration cycle 400 shown in FIG. 11, which is provided between an dryer 308 and a capillary tube 310. A valve 402 is provided.

Thus, when the refrigeration cycle 400 is stopped, the refrigerant does not flow from the high pressure side to the low pressure side by the solenoid valve 402, and the cycle loss can be reduced. FIG. 12 shows the pressure change of each part.

However, in the second conventional example, when the compressor 302 stops, the compressor 3
Since the pressure difference between the inlet and the outlet of the compressor 02 is maintained to be large, a large torque is required when the compressor 302 is started next time, and there is a problem that the compressor 302 cannot be started in the worst case.

Therefore, the first aspect of the present invention is that the pressure difference between the inlet and the outlet does not occur even when the compressor is stopped,
An object of the present invention is to provide a refrigeration cycle of a refrigerator that can be started without requiring a large torque.

(Third Conventional Example) FIG. 13 shows a configuration of a refrigeration cycle 600 according to a third conventional example.

[0012] As shown in FIG.
Is sent to the freezing room 606 and the refrigerating room 608 by the fan 604. The flow of the cool air to the refrigerator compartment 608 was controlled by a damper 610 in the middle of the duct, and the cool air was distributed to the refrigerator compartment 608 and the freezer compartment 606 to be cooled to respective predetermined temperatures.

In this refrigeration cycle 600, since two temperature zones are cooled by one evaporator 602, to cool the refrigerator compartment 608, the refrigerant is evaporated at a low temperature and the temperature inside the refrigerator compartment 608 is reduced by 10%. It was cooled by flowing cold air at a low temperature of ° C. For this reason, the efficiency of the refrigeration cycle 600 viewed from the refrigerator compartment 608 must be low.

(Fourth conventional example) A fourth conventional example is an improvement of the efficiency of the refrigeration cycle 600 of the third conventional example, and FIG. 14 shows the configuration of the refrigeration cycle 700.

As shown in the figure, a refrigeration cycle 700 includes a compressor 702, a condenser 704,
6. The dryer 708 was connected. The flow passage from the dryer 708 was branched into two, and one of the flow passages was connected to a cold room capillary tube 710 and a cold room evaporator 712. The other flow path was connected with the solenoid valve 714 and the freezing room capillary tube 716. The flow path from the refrigerator compartment evaporator 712 and the freezer compartment capillary tube 716 are combined into one flow path, and the freezer compartment evaporator 718 is connected.

In this refrigeration cycle 700, the flow of the refrigerant is controlled by one solenoid valve 714 by providing a difference in the pressure loss between the capillary tubes 710 and 716 as the restriction of the refrigerant. That is, by tightening the throttle of the capillary tube 710 for the refrigerator compartment,
4 opens, the capillary tube 71 for the freezing room is opened.
6, the refrigerant flows to the capillary tube 710 for the refrigerator when the refrigerant is closed.

However, in this refrigeration cycle 700, since it is necessary to provide a difference between the throttles of the two capillary tubes 710 and 716, the degree of freedom of the throttle of the capillary tubes is small, and the optimal cycle cannot be designed. There was a point. As a solution to this, a configuration in which an electromagnetic valve is installed at the entrance of each capillary tube is also conceivable, but there is a problem that the cost increases because two electromagnetic valves are required.

Therefore, the second invention provides a refrigeration cycle in a refrigerator that does not require adjusting the amount of refrigerant by restricting a capillary tube when two evaporators are used.

[0019]

According to a first aspect of the present invention, there is provided a refrigeration cycle for a refrigerator, comprising: a compressor, a condenser, a capillary tube, and an evaporator, which are connected in this order, between the condenser and the capillary tube. A three-way valve was provided in the refrigerant flow path, and a refrigerant bypass pipe was provided from the three-way valve to the compressor.

A refrigeration cycle of a refrigerator according to a second aspect is the refrigerator according to the first aspect, wherein a check valve is provided on a side of the evaporator of a bypass pipe of the refrigerant to the compressor.

A refrigeration cycle of a refrigerator according to claim 3 is the refrigerator according to claim 1, wherein the refrigerant flows to the capillary tube by the three-way valve during the operation of the refrigeration cycle, and the refrigerant flows during the stoppage of the refrigeration cycle. A three-way valve allows the refrigerant to flow to the bypass pipe.

According to a fourth aspect of the present invention, there is provided a refrigerator according to the first aspect, wherein the compressor is a reciprocating compressor.

According to the refrigeration cycle of the refrigerator of the present invention, the compressor and the condenser are connected in this order, and the refrigerant flow path from the condenser is divided into two by a three-way valve, and the refrigerant is divided into the two divided flow paths. The capillary tube and the evaporator for the refrigerator compartment are connected in order, and the capillary tube for the freezer compartment and the evaporator are connected in order to the other of the two divided flow paths.

The refrigeration cycle of a refrigerator according to claim 6 is the refrigerator according to claim 1 or 5, wherein the three-way valve is provided with a refrigerant flow passage inside the three-way valve main body, and the refrigerant flow is provided in one of the flow passages. Is provided, a second outlet for the refrigerant is provided on the other side of the flow path, an inlet for the refrigerant is provided in the middle of the flow path, and the first outlet and the inlet in the flow path are provided. A first valve seat is provided between the second outlet and the inlet in the flow path, a motor is provided on the three-way valve body, and a motor is provided on a rotating shaft of the motor. By providing a male screw rotatably moving along the direction of the flow path inside the three-way valve body, a valve body moving in the flow path so as to close the first valve seat or the second valve seat. It is provided on the male screw.

According to the refrigeration cycle of the refrigerator of the present invention, a three-way valve is provided in the refrigerant flow path between the condenser and the capillary tube, and a refrigerant bypass pipe is provided from the three-way valve to the compressor.

Therefore, by using this bypass pipe, the pressure at the inlet and the outlet of the compressor can be balanced.

According to the refrigeration cycle of the refrigerator of the second aspect, even if high-pressure refrigerant flows through the bypass pipe, the check valve does not cause high-pressure refrigerant to flow through the evaporator.

In the refrigeration cycle of the refrigerator according to the third aspect, during the operation of the refrigeration cycle, the refrigerant can flow to the capillary tube by the three-way valve, and can be cooled by the evaporator. Further, during the stop of the refrigeration cycle, the refrigerant flows to the bypass pipe by the three-way valve, so that the pressure at the inlet and the outlet of the compressor can be balanced.

According to the refrigerating cycle of the refrigerator of the present invention, even if the compressor is a reciprocating compressor, the pressure at the inlet and the outlet can be balanced by the bypass pipe, so that it is difficult to start the compressor. Absent.

According to the refrigeration cycle of the refrigerator of the fifth aspect, the refrigerant can be sent to the capillary tube for the refrigerator compartment and the capillary tube for the freezer compartment by the three-way valve, so that the throttle of the capillary tube is adjusted. Thus, the flow path of the refrigerant can be controlled.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A refrigeration cycle 10 in a refrigerator according to a first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a view showing a refrigerant flow path of a refrigeration cycle 10. As shown in FIG. 1, the refrigeration cycle 10 has a muffler 14, a condenser 16, Pipe 18, dryer 20
Is connected. An outlet A of the dryer 20 is connected to an inlet A of a three-way valve 22, and one outlet B of the three-way valve 22 is connected to a capillary tube 24, an evaporator 26, and a check valve 28. The outlet of the check valve 28 and the inlet of the compressor 12 are connected. The other outlet C of the three-way valve 22 has a bypass pipe 30.
And is connected to the inlet of the compressor 12.

FIG. 2 shows the arrangement of each device in the cabinet 32 of the refrigerator. As shown in FIG.
The compressor 12 is arranged in a machine room 34 of the cabinet 32, the condenser 16 is arranged at the bottom of the cabinet 32, and the evaporator 26 is arranged at the back. In addition, the dew prevention pipe 18 is provided to be bent on the front surface of the cabinet 32.

The refrigeration cycle 10 having the above configuration will be described.

FIG. 3 shows changes in the pressure state of each device when the refrigeration cycle 10 is operated or stopped. Is a three-way valve 2 from the outlet of the compressor 12.
2 indicates the pressure state from the three-way valve 22 to the capillary tube 24, and indicates the evaporator 26 and the check valve 28 from the outlet of the capillary tube 24.
Indicates the pressure state from the check valve 28 to the inlet of the compressor 12.

During operation of the refrigeration cycle 10, the three-way valve 22
Open in the direction of flow from inlet A to outlet B. In FIG. 4, is the condensation pressure and the pressure is high. The refrigerant passing through the capillary tube 24 has a low pressure, and has a vaporization pressure. The inside of the refrigerator is cooled to a predetermined temperature, and the refrigeration cycle 10 stops.

At the same time as the refrigerating cycle 10 is stopped, the three-way valve 2
2 switches the flow path and opens in the direction from the inlet A to the outlet C. The refrigerant on the high pressure side such as the condenser 16 flows into the inlet of the compressor 12 through the bypass pipe 30. As a result, the pressure becomes the same. Further, since the inlet A and the outlet B of the three-way valve 22 and the check valve 28 are closed,
And remain at low pressure.

Next, when the internal temperature rises and the compressor 12 is started, the pressure at the inlet and the outlet of the reciprocating compressor 12 is balanced, so that the required starting torque of the compressor 12 is small. . By switching the flow path of the three-way valve 22 after the compressor 12 is started, the pressure increase immediately after the start is small, so that the acceleration torque is small. Further, even if a pressure difference occurs by switching the three-way valve 22 after the operation of the compressor 12 is stabilized, the compressor 12 can continue to operate without stopping because of the inertia due to the operation.

With the refrigeration cycle 10 described above, when the refrigeration cycle 10 is shifted from the stopped state to the operating state, the pressures at the inlet and the outlet of the compressor 12 are balanced, so that the effect that the starting torque is small is sufficient. is there.

Although the reciprocating compressor 12 is used in the above embodiment, a rotary compressor may be used instead.

Next, the structure of the three-way valve 22 used in the above embodiment will be described with reference to FIG. FIG. 4 is a heavy sectional view of the three-way valve 22.

The three-way valve 22 is provided with a flow path 38 in the axial direction inside a substantially cylindrical main body 36. This channel 3
An outlet B is provided at the lower end of 8 and an outlet C is provided at the upper end. An inlet A is provided in the middle of the flow path 38. The outlet C is provided so as to be substantially orthogonal to the axial flow path 38.

A first valve seat 40 is provided above the outlet B, and a second valve seat 42 is provided below the outlet C.

A rotor 46 constituting the motor 44 is built in the upper part of the main body 36. Further, a stator 48 constituting the motor 44 is provided outside the upper portion of the main body 36.

The rotor 46 is constantly urged downward by a spring 50 so that the rotation of the rotor 46 is stabilized.
A male screw portion 54 is provided at a tip of a shaft 52 which is a rotation shaft of the rotor 46, and is screwed to a female screw portion 56 provided on the main body 36 so as to be vertically movable. A spring receiving portion 58 is provided below the male screw portion 54 via a coil type spring 60. A rod-shaped moving portion 62 is provided from the lower end of the spring receiving portion 58, and a spherical valve body 64 is provided at the tip thereof. This valve body 64
8 and can close either the first valve seat 40 or the second valve seat 42.

An operation state of the three-way valve 22 having the above configuration will be described.

When the valve body 64 is located at the lowermost position, the first valve seat 40 is closed, the second valve seat 42 is opened, and the refrigerant flowing from the inlet A passes through the second valve seat 42 and exits. Flow to C.

When a current is applied to the motor 44 in this state, the rotor 46 rotates and the male screw portion 54 moves upward.
Then, the spring receiving portion 58 and the moving portion 6 connected thereto are connected.
2 and the valve body 64 move upward to open the first valve seat 40 and conversely close the second valve seat 42. Thereby, the refrigerant flowing from the inlet A flows to the outlet B.

When the motor 44 is rotated in the reverse direction, the rotor 46 rotates in the reverse direction, and moves the valve body 64 downward. Thereby, the first valve seat 40 is closed, and the second valve seat 42 is opened.

The three-way valve 2 incorporating such a motor 44
By providing 2, the sound is quiet even if the three-way valve 22 operates, low power consumption can be realized, and long-term reliability can be improved.

(Second Embodiment) A refrigeration cycle 100 according to a second embodiment of the present invention will be described with reference to FIGS.

FIG. 5 shows a refrigerant flow path of the refrigeration cycle 100. As shown in this figure, the outlet of the compressor 102 has a condenser 104, a dew-proof pipe 106, a dryer 1
08 and the three-way valve 110 are connected. Three-way valve 110
One of the outlets B has a capillary tube 11 for a refrigerator.
2 and the evaporator 114 for the refrigerator compartment are connected.
A capillary tube 116 for the freezer compartment and an evaporator 118 for the freezer compartment are provided at the other outlet C of the three-way valve 110.
Is connected. Then, the refrigerator compartment evaporator 11
4 and the outlet of the freezer evaporator 118 are connected by a suction pipe 120 to the compressor 10.
2 is connected to the entrance.

FIG. 6 shows an arrangement state of each device in the refrigerator of the refrigeration cycle 100.

As shown in this figure, the compressor 102 is disposed in the machine room 124 of the refrigerator cabinet 122, and the condenser 104 is disposed at the bottom of the cabinet 122.

An evaporator 114 for the refrigerator compartment is arranged on the upper rear side of the cabinet 122, and an evaporator 118 for the freezer compartment is arranged below the refrigerator. Further, the dew prevention pipe 106 is provided on the front surface of the cabinet 122.

According to the refrigeration cycle 100, when the temperature of the freezing room is high and it is necessary to cool the freezing room,
The three-way valve 110 is moved so that the refrigerant flows through the capillary tube 116 connected to the freezer, and the refrigerant is evaporated by the freezer evaporator 118 to cool the freezer.

Conversely, when the temperature of the refrigerator compartment is high and the refrigerator compartment needs to be cooled, the three-way valve 110 is switched so that the refrigerant flows to the refrigerator compartment evaporator 114.

As described above, since each room is cooled in another mode, the refrigeration cycle 100 can be operated at an appropriate refrigerant evaporation temperature. When the refrigerator is cooled, it is possible to operate the refrigerant cycle at a high evaporation temperature. Cycle efficiency can be improved.

The three-way valve 110 has the same structure as the three-way valve 22 described above.

Third Embodiment A refrigeration cycle 200 according to a third embodiment will be described with reference to FIGS.

The difference between the refrigeration cycle 200 of this embodiment and the refrigeration cycle 100 of the second embodiment lies in the position of the freezer evaporator 118. That is, in the refrigeration cycle 200, the outlet of the refrigerator compartment evaporator 114 and the outlet of the freezer capillary tube 116 are connected to one, and connected to the inlet of the freezer compartment evaporator 118.

With this refrigeration cycle 200, when the temperature of the freezing room is high and it is necessary to cool the freezing room,
The three-way valve 110 is moved so that the refrigerant flows through the capillary tube 116 connected to the freezer, and the refrigerant is evaporated by the freezer evaporator 118 to cool the freezer.

Conversely, when the temperature of the refrigerator compartment is high and the refrigerator compartment needs to be cooled, the three-way valve 110 is switched so that the refrigerant flows to the refrigerator compartment evaporator 114. However, even if such switching is performed, the freezer evaporator 11
Since the refrigerant flows in 8, only the refrigerator compartment is cooled by stopping a fan (not shown) that sends cool air to the freezer compartment.

In this refrigeration cycle 200, the freezing compartment and the refrigerating compartment are cooled in different modes, respectively, so that the efficiency of the refrigeration cycle can be improved.

[0065]

As described above, in the refrigeration cycle in the refrigerator according to any one of the first to fourth aspects, the pressure difference between the inlet and the outlet of the compressor can be eliminated by providing the bypass pipe. When starting, the starting torque can be reduced.

According to the refrigerating cycle of the refrigerator of the fifth aspect, the flow path of the refrigerant can be switched by the three-way valve, so that the refrigerating room and the freezing room can be efficiently cooled, respectively.

[Brief description of the drawings]

FIG. 1 is a refrigerant flow path of a refrigeration cycle of a first embodiment.

FIG. 2 is a layout diagram of the refrigerator in the refrigeration cycle.

FIG. 3 is a graph showing the pressure of each part in each cycle.

FIG. 4 is a longitudinal sectional view of a three-way valve.

FIG. 5 is a refrigerant flow path of a refrigeration cycle of a second embodiment.

FIG. 6 is a layout diagram of a refrigerator of the refrigeration cycle.

FIG. 7 is a refrigerant flow path of a refrigeration cycle of a third embodiment.

FIG. 8 is a layout diagram of the refrigerator in the refrigeration cycle.

FIG. 9 is a refrigerant flow path of a first conventional example.

FIG. 10 is a graph showing the pressure of each part of each cycle of the refrigeration cycle.

FIG. 11 is a refrigerant flow path of a second conventional example.

FIG. 12 is a graph showing the pressure of each part of each cycle in the refrigeration cycle.

FIG. 13 is a layout diagram of a refrigeration cycle of a third conventional example.

FIG. 14 is a refrigerant flow path of a refrigeration cycle of a fourth conventional example.

[Explanation of symbols]

 Reference Signs List 10 Refrigeration cycle 12 Compressor 16 Condenser 22 Three-way valve 24 Capillary tube 26 Evaporator 28 Check valve 30 Bypass pipe

Claims (6)

[Claims] 1. A refrigerating cycle of a refrigerator in which a compressor, a condenser, a capillary tube, and an evaporator are connected in this order, a three-way valve is provided in a refrigerant flow path between the condenser and the capillary tube, and the three-way valve is connected to the compressor. A refrigeration cycle for a refrigerator, comprising a refrigerant bypass pipe. 2. The refrigerating cycle of a refrigerator according to claim 1, wherein a check valve is provided on a side of the evaporator of a bypass pipe of the refrigerant to the compressor. 3. The three-way valve allows the refrigerant to flow to the capillary tube during operation of the refrigeration cycle, and the three-way valve allows the refrigerant to flow to the bypass pipe while the refrigeration cycle is stopped. The refrigeration cycle of a refrigerator according to claim 1, wherein: 4. The refrigeration cycle of a refrigerator according to claim 1, wherein said compressor is a reciprocating compressor. 5. A compressor and a condenser are connected in this order, the flow path of the refrigerant from the condenser is divided into two by a three-way valve, and one of the two divided flow paths is a capillary tube for a refrigerator and an evaporator. And a capillary tube for a freezer and an evaporator are connected in order to the other of the two flow paths. 6. The three-way valve, wherein a refrigerant flow path is provided inside the three-way valve main body, a first refrigerant outlet is provided in one of the flow paths, and a second refrigerant outlet is provided in the other of the flow paths. A refrigerant inlet is provided in the middle of the flow path, a first valve seat is provided between the first outlet and the inlet in the flow path, and a second outlet is provided in the flow path. A second valve seat is provided between the three-way valve body and the three-way valve body, and a motor is provided on the three-way valve body. The valve body according to claim 1 or 5, wherein a valve body that moves inside the flow passage so as to close the first valve seat or the second valve seat is provided inside the male screw. Refrigeration cycle of the refrigerator.