JPH08271115A - Refrigerator - Google Patents

Abstract

PURPOSE: To provide a refrigerator in which a thermal radiation can be assured even if a fin tube is clogged. CONSTITUTION: A machine chamber 12 is arranged at an upper part of a refrigerating chamber. A fin tube 38 is arranged at a front surface of the machine chamber 12. A fan 32 is arranged behind the fin tube 38, further a wire condensor 40 is installed behind the fan 32. A thermal radiation quantity of the wire condensor 40 is 23% or more of the entire thermal radiation quantity.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Conventionally, compressors, condensers,
There is a refrigerator in which refrigeration cycle units such as an evaporator are centrally installed on the upper part of the main body of a refrigerating room (hereinafter referred to as a "comp top refrigerator").

In this comp top refrigerator, the heat from the refrigeration cycle is taken into consideration in consideration of space saving of the refrigeration cycle unit and separability from the body of the refrigerator.
Heat was dissipated only by the fin tube.

[0004]

However, when the fin tube is clogged with dust or the like and causes heat radiation failure, there is no other heat radiation means, and the refrigeration cycle overheats, causing internal heat in the compressor. There is a problem that the temperature of the lubricating oil rises abnormally and the compressor fails.

Therefore, the present invention provides a refrigerator capable of ensuring heat dissipation even if the fin tube is clogged.

[0006]

The refrigerator according to claim 1 comprises a fin tube and an auxiliary condenser as a heat dissipation member for a refrigerating cycle of the refrigerator, an air intake is provided in the body of the refrigerator, and the air intake is provided in the air intake. Facing the air intake surface of the fin tube, and a fan is provided on the downstream side of the fin tube to force the air to flow from the air intake port to the fin tube. The auxiliary capacitor is provided on the side.

According to a second aspect of the present invention, in the refrigerator of the first aspect, the composition ratio of the fin tube and the auxiliary condenser is set so that the minimum necessary heat radiation amount of the refrigeration cycle can be secured by the heat radiation amount of the auxiliary condenser. It was done.

According to a third aspect of the present invention, in the refrigerator of the second aspect, the fin tube and the auxiliary condenser are configured such that the heat radiation amount of the auxiliary condenser is 23% or more of the total heat radiation amount of the refrigeration cycle. The ratio is set.

According to a fourth aspect of the present invention, in the refrigerator of the first aspect, a ventilation port and a ventilation path for directly supplying air to the auxiliary condenser are provided.

According to a fifth aspect of the present invention, in the refrigerator of the fourth aspect, the air intake port and the ventilation port are shared.
The ventilation passage is provided around the fin tube.

According to a sixth aspect of the present invention, in the fifth aspect, the cross-sectional area of the ventilation passage is 30% or less of the area of the air intake surface of the fin tube.

According to a seventh aspect of the present invention, in the refrigerator of the fifth aspect, the air intake port and the ventilation port are shared.
The arrangement density of the fins on the air intake surface of the fin tube is changed so that the position where the arrangement density of the fins is low is the ventilation passage.

[0013]

[Operation] The heat radiation state of the refrigerator according to claim 1 will be described.

Since the air is forced to flow from the air intake port through the fin tube by the fan, heat dissipation of the fin tube is promoted. On the other hand, the auxiliary condenser provided on the downstream side of the fin tube also promotes heat dissipation by the air flowing from the fin tube.

The heat radiation state of the refrigerator of claim 2 will be described.

The heat from the refrigeration cycle is radiated from both the fin tube and the auxiliary condenser. In this case, the heat dissipation of the auxiliary capacitor is configured to secure the minimum necessary heat dissipation of the refrigeration cycle, so even if the fin tubes are clogged with dust etc. The heat from the auxiliary capacitor is dissipated. The "minimum necessary heat radiation amount" means the heat radiation amount that must radiate at least the heat from the refrigeration cycle so that the refrigeration cycle does not rise above the allowable temperature.

The heat radiation state of the refrigerator of claim 3 will be described.

Since the composition ratio of the fin tube and the auxiliary capacitor is set so that the heat dissipation amount of the auxiliary capacitor is 23% or more of the total heat dissipation amount of the refrigeration cycle, the auxiliary capacitor ensures the minimum necessary heat dissipation amount. be able to.

The heat radiation state of the refrigerator of claim 4 will be described.

Since the air can be directly supplied to the auxiliary condenser by providing the ventilation port and the ventilation passage,
The heat dissipation of the auxiliary capacitor can be promoted.

The heat radiation state of the refrigerator of claim 5 will be described.

Since the opening area of the ventilation port is 30% or more of the area of the air intake surface of the fin tube, the air directly supplied to the auxiliary condenser can be kept at a minimum, which promotes heat dissipation of the auxiliary condenser. can do.

The heat radiation state of the refrigerator of claim 6 will be described.

A space can be used without waste by providing an air intake port and a ventilation port as well as providing a ventilation path around the fin tube.

The heat radiation state of the refrigerator of claim 7 will be described.

Since the air intake port and the ventilation port are also used and the arrangement density of the fins on the air intake surface of the fin tube is changed so as to serve as the ventilation port at the position where the fin arrangement density is low, the air flows in from the air intake port. The generated air is directly supplied to the auxiliary condenser through the ventilation passage where the fin arrangement density is small.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A comptop refrigerator 10 which is an embodiment of the present invention will be described below with reference to FIGS.

Reference numeral 12 is a machine room, which is a refrigerator 10.
It is provided on the ceiling of the main body 14. The inside of the machine room 12 is divided into the left and right at the center, the right side constitutes the heat insulation chamber 16, and the left side constitutes the heat dissipation chamber 18. Insulation room 16
Is covered with a heat insulating member 17 on all four sides thereof.

Reference numeral 20 is an evaporator provided inside the heat insulation chamber 16. Behind the evaporator 20, a fan 22 for an evaporator is provided.

Reference numeral 24 is a partition wall that partitions the heat dissipation chamber 18 in the front-rear direction. The partition wall 24 divides the heat dissipation chamber 18 into a front heat dissipation chamber 26 and a rear heat dissipation chamber 28.

Reference numeral 30 is a compressor mounted in the rear heat radiation chamber 28.

Reference numeral 32 is a bell mouth type fan provided on the partition wall 24, forcibly sending air from the front heat radiation chamber 26 toward the rear heat radiation chamber 28.

Reference numeral 34 is an air intake provided on the front surface of the front heat radiation chamber 26.

Reference numeral 36 is an air outlet provided on the rear wall of the rear heat radiation chamber 28.

Reference numeral 38 is a fin tube provided in the front part of the front heat radiation chamber 26 facing the air intake port 34.
The fins of the fin tube 38 are provided in three rows in the front-rear direction, and are provided at equal intervals in the left-right direction.
In addition, a space is formed between the upper surface of the fin tube 38 and the ceiling surface of the front heat dissipation chamber 26, and this space serves as a ventilation path 46 for sending air directly to the fan 32. The cross-sectional area of the ventilation passage 46 is configured to be about 30% of the air intake surface that is the front surface of the fin tube 38.

Reference numeral 40 denotes a wire capacitor formed in a substantially plate shape, which is attached in close contact with the ceiling surface of the rear heat radiation chamber 28. The ratio of the heat dissipation amount of the wire capacitor 40 to the heat dissipation amount of the fin tube 38 (hereinafter, referred to as a composition ratio) is 23 so that the heat dissipation amount of the wire capacitor 40 can ensure the minimum necessary heat dissipation amount of the entire heat dissipation amount.
It is configured to be%.

Reference numeral 42 is an air filter provided at the air intake 34.

First, the structure of the refrigeration cycle unit of the refrigerator 10 will be described with reference to FIG.

By the compressor 1, the refrigerant is sent to the wire condenser 40 and radiates heat, and is sent to the fin tubes 38 to further promote heat dissipation. The refrigerant discharged from the fin tube 38 reaches the evaporator 20 via the capillary tube 44, the temperature of the refrigerant decreases, and the cooling effect is exerted.

Next, the flow of air in the heat dissipation chamber 18 will be described.

The air flowing in from the air intake port 34 passes through the air filter 42 to remove dust and the like, and reaches the ventilation passage 46 and the fin tube 38. The air reaching the fin tubes 38 promotes heat dissipation from the fin tubes 38 and reaches the position of the fan 32. Further, the air flowing into the ventilation passage 46 reaches the fan 32 directly and is forcibly sent to the rear heat radiation chamber 28. This air is a wire condenser 40
And the compressor 30 are cooled and discharged from the air discharge port 36 rearward. Further, since the wire capacitor 40 is closely attached and fixed to the rear side of the ceiling surface of the rear heat radiation chamber 28, heat radiation is promoted through the ceiling surface, and the number of assembling steps can be reduced.

The reason why the heat dissipation amount of the wire capacitor 40 is 23% of the total heat dissipation amount will be described.

Generally, the characteristic of the compressor 30 is that the coefficient of performance is 160%, the compression efficiency is 0.8, the mechanical efficiency is 0.9, and the electric motor efficiency is 0.7.

When the compressor 30 is overheated and exceeds the heat resistant temperature of the winding of the electric motor for moving the compressor 30, the winding is burned. In order to prevent this, it is necessary to secure at least heat radiation corresponding to the loss of the motor, which is a condition for preventing overheating of the compressor 30 and ensuring its reliability.

Considering the above points, assuming that the work from the compressor 30 is 100, the heat of vaporization is 1 from the coefficient of performance.
It becomes 60. Therefore, the required heat radiation amount is 260, which is the added value of these.

Further, the power required for the compressor to perform 100 jobs is 100 / (0.8 × 0.
9 × 0.7) = about 200. Of this 200 power, the amount of heat radiated as motor loss is 200 x (1.0
-0.7) = 60. Therefore, if only this heat radiation amount is secured at a minimum, the winding temperature does not rise and the compressor 30 does not overheat. Therefore, the ratio to the required heat radiation amount is 60/260 = 23 (%). This 23% is the minimum required heat radiation amount.

In order to confirm the above theory, FIG. 7 shows the result of an experiment conducted by changing the composition ratio of the fin tube 38 and the wire capacitor 40.

The horizontal axis in FIG. 7 indicates the fin tube 38.
And the composition ratio of the wire condenser 40, and the vertical axis indicates each position in the refrigerator 10 (the outlet of the compressor 30, the inside of the freezing chamber, the inlet of the evaporator 20, the compressor 30).
The surface temperature of each) is shown. Also, the solid line is
The outside air temperature is the temperature at each location at 30 ° C., and the dotted lines are the respective temperatures at the outside air temperature of 35 ° C. These temperatures are measured by forcibly blocking the heat radiation from the fin tube 38.

According to this, when the composition ratio of the wire capacitor 40 is about 23% or more, each temperature does not rise so much, but when the composition ratio is 23% or less, the temperature at each place rises sharply. A particular problem is the surface temperature of the compressor 30, and when the composition ratio exceeds 23%, the surface temperature exceeds 110 ° C. This means that the upper limit of the temperature of the lubricating oil inside the compressor 30 has reached 110 ° C. Therefore, in order to keep the lubricating oil temperature of the compressor 30 appropriate, the composition ratio of the wire condenser 40 needs to be 23% or more.

As described above, when the refrigerator 10 of the above embodiment is used, even if the fin tubes 38 are clogged due to the adhesion of dust and the heat radiation effect is reduced, the composition ratio of the wire capacitor 40 is 23. If it is set to be not less than%, the minimum required heat radiation amount can be secured, and the rise of the lubricating oil temperature of the compressor 30 can be prevented.

The relationship between the area of the air intake surface of the fin tube 38 and the cross-sectional area of the ventilation passage 46 will be described.

When the ventilation passage 46 is provided above the fin tubes 38 and the cross-sectional area of the ventilation passages 46 is made too large, the pressure loss in the ventilation passages 46 becomes smaller than the pressure loss in the fin tubes 38, so that the air flow is reduced. The air that has flowed in through the intake port 34 does not flow into the fin tube 38, and the air passage 46
Flows to.

When most of the air flows into the ventilation passage 46 in this way, heat dissipation from the fin tubes 38 is not promoted, and the purpose cannot be achieved.

Therefore, it is necessary to make the cross-sectional area of the ventilation passage 46 smaller than the cross-sectional area of the air intake surface of the fin tube 38.

On the other hand, if the cross-sectional area of the ventilation passage 46 is made too small, air is directly taken in from the ventilation passage 46 and the fan 32 is introduced.
I can't achieve the goal of flushing. Therefore, it is necessary to find a position where an appropriate balance between the two can be obtained. Hereinafter, the result of the experiment conducted to obtain such a position will be described.

The graph of FIG. 8 shows the result of an experiment in which the fin tubes 38 are provided in three rows. In FIG. 8, the horizontal axis represents the ratio of the cross-sectional areas of the air intake surface of the ventilation passage 46 and the fin tube 38, and the vertical axis represents the location of the refrigerator (the outlet of the compressor 30, the freezer compartment, the inlet of the evaporator 20). Shows the temperature.

According to this, when the ratio of the cross-sectional area exceeds 30%, each temperature sharply rises. That is, when the ratio of the cross-sectional area is 30% or more, it means that the heat radiation efficiency from the fin tube 38 is remarkably reduced, and therefore, the ratio of the cross-sectional area is preferably 30% or less.

In the above embodiment, the fin tube 38 is used.
Was 3 rows, but when it became 2 rows or 1 row, the pressure loss in the fin tube 38 was 1/2, 1 /, respectively.
It will be 3. Therefore, the pressure loss of the ventilation passage 46 corresponding to this also changes. Here, since the pressure loss in the ventilation passage 46 is a dynamic loss and is proportional to the square of the wind speed, the area of the ventilation passage 46 having the same pressure loss as that of the two rows of fin tubes 38 is 42%, which is 1 52% for row fin tubes
Becomes

FIG. 9 shows a modification of the ventilation passage 46, in which the ventilation passage 46 is provided below the central portion of the fin tube 38.

FIG. 10 shows a second modification of the ventilation passage 46 in which the fin arrangement density of the fin tubes 38 is smaller on both sides and larger on the central portion. As a result, the ventilation passages 46 are located on both side portions where the fins are sparsely arranged.

FIG. 11 shows a third modification of the ventilation passage 46, in which the fin arrangement density of the fin tubes 38 is made smaller toward the central portion, and the ventilation passage 46 is arranged at this central portion. .

In the above embodiment, the air filter 42 is used.
Was provided over the entire surface of the air intake port 34, but instead of this, it may be provided only at a position corresponding to the fin tube 38 and opened at a position facing the ventilation passage 46.

A plate capacitor may be provided instead of the wire capacitor 40.

Although the above-described embodiment is the comp-top refrigerator 10, it may be applied to one in which the machine room is arranged at the bottom of the refrigerator.

[0065]

According to the refrigerator of the first aspect, since the heat dissipation member is composed of the fin tube and the auxiliary capacitor, even if the fin tube is clogged with dust or the like to reduce the heat dissipation efficiency, the auxiliary capacitor dissipates the heat. Is ensured, the refrigeration cycle does not break down.

According to the refrigerator of claim 2, since the heat radiation amount of the auxiliary capacitor is set so as to ensure the minimum necessary heat radiation amount of the refrigeration cycle, even if the fin tube does not radiate heat at all, the refrigeration cycle Does not break down.

According to the third aspect of the present invention, since the heat dissipation amount of the auxiliary condenser is 23% or more of the necessary heat dissipation amount of the refrigeration cycle, the refrigeration cycle does not fail due to overheating. .

According to the refrigerator of claim 4, since air is directly supplied to the auxiliary condenser from the ventilation port and the ventilation passage,
The heat dissipation can be promoted.

In the refrigerator according to the fifth aspect, since the opening area of the ventilation port is 30% or less of the area of the air intake surface of the fin tube, air can be reliably supplied to the fin tube. The heat dissipation efficiency of does not decrease.

According to the sixth aspect of the present invention, the air intake can be made compact because the air intake and the air intake are combined and the air passage is provided around the fin tube.

In the refrigerator according to the seventh aspect, the air intake structure can be made compact by changing the arrangement density of the fins and providing the ventilation passages inside the fin tubes.

[Brief description of drawings]

FIG. 1 is a front view of a refrigerator according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a machine room of the refrigerator shown in the previous figure.

3 is a cross-sectional view taken along the line AA in FIG.

FIG. 4 is a sectional view taken along line BB in FIG.

5 is a sectional view taken along line CC in FIG.

FIG. 6 is a structural diagram of a unit of a refrigeration cycle.

FIG. 7 is a graph showing the temperature at each place when the composition ratio of the fin tube and the wire capacitor is changed.

FIG. 8 is a graph of temperature at each place when the composition ratio of the air intake surface of the ventilation passage and the air intake surface of the fin tube is changed.

FIG. 9 is a front view of a first modification of the ventilation passage.

FIG. 10 is a front view of the second modification of the same.

FIG. 11 is also a front view of the third modification.

[Explanation of symbols]

 10 Refrigerator 12 Machine Room 14 Main Body 16 Insulation Room 18 Heat Radiation Room 20 Evaporator 22 Evaporator Fan 24 Partition Wall 26 Front Heat Radiation Room 28 Rear Heat Radiation Room 30 Compressor 32 Fan 34 Air Intake 36 Air Exhaust 38 Fin Tube 40 Wire Condenser 42 Air Filter 46 Ventilation path

Claims (7)

[Claims] 1. A heat dissipating member for a refrigerating cycle of a refrigerator comprises a fin tube and an auxiliary condenser, an air intake is provided in the body of the refrigerator, and an air intake surface of the fin tube faces the air intake. A fan is provided on the downstream side of the fin tube and the auxiliary condenser is provided on the downstream side of the fin tube in order to forcibly flow air from the air intake port to the fin tube. And a refrigerator. 2. The composition ratio of the fin tube and the auxiliary capacitor is set so that the minimum required heat radiation amount of the refrigeration cycle can be secured by the heat radiation amount of the auxiliary capacitor. refrigerator. 3. The composition ratio of the fin tube and the auxiliary capacitor is set so that the heat dissipation amount of the auxiliary capacitor is 23% or more of the total heat dissipation amount of the refrigeration cycle. Item 2. The refrigerator according to item 2. 4. The refrigerator according to claim 1, wherein a ventilation port and a ventilation path for directly supplying air to the auxiliary condenser are provided. 5. The refrigerator according to claim 4, wherein the air intake port is also used as the ventilation port, and the ventilation path is provided around the fin tube. 6. The refrigerator according to claim 5, wherein the cross-sectional area of the ventilation passage is 30% or less of the area of the air intake surface of the fin tube. 7. The air intake opening and the ventilation opening are shared, the fin arrangement density is changed on the air intake surface of the fin tube, and a position where the fin arrangement density is small is used as the ventilation passage. The refrigerator according to claim 5, wherein: