JP2003083665A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator that can efficiently refrigerate and freeze vegetables by improving the heat exchanger effectiveness without making the volume of a vegetable room smaller. SOLUTION: This refrigerator is provided with an evaporator constituted by attaching a plurality of heat exchanger fins 28 to a refrigerant pipeline 27 at intervals in the longitudinal direction of the pipeline 27. The arragning intervals of the fins 28 on the pipeline 27 on the refrigerant inlet side of the evaporator is made longer than those of the fins 28 on the pipeline 27 on the refrigerant outlet side of the evaporator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator in which an evaporator having heat exchange fins is attached to the surface of a refrigerant pipe.

[0002]

2. Description of the Related Art Conventionally, a household refrigerator of this kind has been disclosed in, for example, Japanese Patent Laid-Open No. 8-338681 (F25D23 / 00).
As shown in Fig. 2, it consists of an insulation box body filled with foam insulation such as polyurethane foam by an in-situ foaming method between an outer box made of steel plate and an inner box made of hard resin. ) Is divided into a plurality of compartments to form a freezer compartment, a refrigerator compartment, a vegetable compartment, and the like. An evaporator is installed in the rear of the freezer compartment, and the cool air cooled by the evaporator is circulated in each compartment to cool it to a predetermined temperature.

A machine room is formed in the lower part of the heat insulating box, and a compressor and a condenser heat which form a refrigerating cycle, and a fan for cooling them are installed in the machine room. . And while the compressor is running
The blower was also operated, and air was cooled by ventilating the compressor and the condenser.

As the evaporator, a heat exchanger which is long in the vertical direction and has heat exchange fins provided on the surface of the refrigerant pipe is adopted. By the way, as a refrigerator, a refrigerator, a vegetable compartment, and a freezer are generally arranged from the top. In this general refrigerator, the evaporator is general because it is arranged in the cooling chamber behind the freezing chamber. However, as mentioned above,
Since the machine room is arranged in the lower part of the refrigerator, the capacity is not sufficient only in the rear of the freezing room, and the cooling room also extends to the rear of the vegetable room. For this reason, there was a fear that the rear of the vegetable compartment was too cold. In order to prevent this, the heat insulating wall between the rear of the vegetable compartment and the cooling compartment is thickened, or a heat transfer heater is arranged behind the vegetable compartment.

[0005]

Therefore, an evaporator having a short length in the vertical direction and a long length in the depth direction of the refrigerator is adopted, and the cooling chamber is provided only behind the freezing chamber. Can be considered. Ideally, the refrigerator should be designed so that the cold air returning to the evaporator flows evenly into the evaporator even when the length in the depth direction is increased. However, in reality, there is a difference in the amount of cold air flowing between the front and the rear of the evaporator. The present invention has been made in view of the above points, and it is not a refrigerator in which cold air uniformly returns to the evaporator, and a refrigerator having good cooling efficiency even if cold air does not uniformly return to the evaporator. With the goal.

[0006]

According to a first aspect of the present invention, there is provided a refrigerator including an evaporator in which a plurality of heat exchange fins are mounted at intervals in a length direction of a refrigerant pipe. Refrigerator characterized in that the pitch of the heat exchange fins in the refrigerant pipe on the refrigerant inflow side is arranged large, and the pitch of the heat exchange fins in the refrigerant pipe on the refrigerant outlet side of the evaporator is arranged small. Is. According to the invention as set forth in claim 1, the heat exchange transfer rate in the pipe on the refrigerant outlet side of the evaporator is high, and the pitch of the heat exchange fins on the refrigerant outlet side of the evaporator is made small to perform heat exchange in this region. Efficiency is improved.

The invention according to claim 2 is provided with a refrigerating evaporator for a refrigerating temperature zone chamber and a freezing evaporator for a freezing temperature zone chamber, and a freezing evaporator for a freezing temperature zone chamber. The pitch of the heat exchange fins in the refrigerant pipe on the refrigerant inflow side of the refrigerator is arranged to be large, and the pitch of the heat exchange fins in the refrigerant pipe on the refrigerant outlet side of the refrigerating evaporator is arranged to be small. The refrigerator according to claim 1, wherein the refrigerator is a refrigerator. According to the invention as set forth in claim 2, the in-pipe heat exchange transfer coefficient on the refrigerant outlet side of the refrigerating evaporator for the refrigerating temperature zone chamber is high, and the refrigerant flow of the refrigerating evaporator for the refrigerating temperature zone chamber is high. The pitch of the heat exchange fins on the outlet side is reduced to improve the heat exchange efficiency in this region.

According to a third aspect of the present invention, an evaporator having a plurality of heat exchange fins mounted at intervals in the lengthwise direction of the refrigerant pipe is provided, and return cold air is passed upward from below the evaporator. In the refrigerator, a pitch of the heat exchange fins is made smaller in an area where the amount of cold air passing through the evaporator is larger than that in an area where the amount of cold air passing through the evaporator is small. According to the third aspect of the invention, the heat exchange transfer coefficient in the pipe is high in the region where the amount of cold air is large, and when the pitch of the heat exchange fins in the region where the amount of return cool air in the evaporator is large is reduced, the heat exchange in this region is performed. Efficiency is improved.

According to a fourth aspect of the present invention, there is provided an evaporator in which a plurality of heat exchange fins are attached at intervals in the lengthwise direction of the refrigerant pipe, and the return cool air is passed upward from below the evaporator. In a refrigerator, the amount of cold air passing through the evaporator is biased rearward from the front, the refrigerant pipe is meandered so that the refrigerant flows rearward from the front, and the pitch of the heat exchange fins on the front side is increased. The refrigerator according to claim 3, wherein the pitch of the heat exchange fins on the rear side is reduced. According to the invention as set forth in claim 4, even if a non-uniform flow of the return cool air occurs, the rear evaporator has a large amount of cool air and a high heat transfer coefficient in the pipe, and is used for heat exchange of the evaporator in this region. The fin pitch is reduced to improve the heat exchange efficiency in this region.

The invention according to claim 5 is provided with a refrigerating evaporator for a refrigerating temperature zone chamber and a freezing evaporator for a freezing temperature zone chamber, and a freezing evaporator for a freezing temperature zone chamber. The container is claim 4.
The refrigerator according to claim 4, which is the evaporator according to claim 4. According to the invention as set forth in claim 5, the pitch of the heat exchange fins of the freezing evaporator for the freezing temperature zone chamber is set to a predetermined relationship, and the return cold air flowing into the evaporator is efficient. The cooling air is supplied to the freezing temperature zone chamber.

According to a sixth aspect of the present invention, a machine room is provided in the lower rear part, a freezing temperature zone chamber is provided in the lowermost stage, and any one of the first to fifth aspects is provided behind the freezing temperature zone chamber. The refrigerator according to any one of claims 1 to 5, further comprising a cooling chamber provided with the evaporator according to claim 1, wherein the cooling chamber does not extend to the refrigerating temperature zone chamber. According to the invention as set forth in claim 6, in the cooling chamber provided behind the refrigeration temperature zone chamber and provided with the evaporator, even if a non-uniform flow of the return cool air occurs, the amount of cold air in the evaporator on the rear side is small. There are many and the heat transfer coefficient in the pipe is high, and the pitch of the heat exchange fins of the evaporator in this area is made small to improve the heat exchange efficiency in this area and the temperature zone for refrigeration does not become too cold. .

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a front view of the refrigerator of the present invention, FIG. 2 is a vertical side view of the refrigerator of the present invention, FIG. 3 is a perspective view of an essential part of an evaporator in the refrigerator of the present invention, and FIG. 4 is a refrigerator of the present invention. FIG. 6 is a front view of an essential part showing an arrangement example of the refrigerant pipes and heat exchange fins of the evaporator in FIG. 5, FIG. 5 is a side view showing an arrangement example of the refrigerant pipes and heat exchange fins of the evaporator in the refrigerator of the present invention, FIG. FIG. 7 is a graph showing heat exchange efficiency in the pipe of the evaporator of the refrigerator of the present invention, and FIG. 7 is an explanatory view showing another arrangement example of the refrigerant pipes and heat exchange fins of the evaporator of the refrigerator of the present invention.

The refrigerator 1 is composed of an outer box made of steel plate and a heat-insulating box body 2 having a front opening formed by filling a heat-insulating material such as polyurethane foam between the inner boxes made of hard resin such as ABS by an in-situ foaming method. ing. The inside of this heat insulating box 2 is the heat insulating box 2
Is divided into upper and lower parts by a partition wall 2A composed of a heat insulating wall integrally formed with the above, and the inside of the heat insulating box 2 above the partition wall 2A is vertically separated by an upper partition member 2B.

A refrigerating chamber 3 is defined above the upper partition member 2B, and a vegetable chamber 4 is defined between the upper partition member 2B and the partition wall 2A. Further, the opening edge of the heat insulating box 2 below the partition wall 2A is vertically divided by the lower partition member 2C.
The lower side of C is the freezer compartment 7. Further, the space between the partition wall 2A and the lower partition member 2C is further divided into left and right sides, and the left side is an ice making chamber 5 and the right side is a select chamber 6.

The front opening of the refrigerating compartment 3 is openably and closably closed by a rotatable heat insulating door 9, and the refrigerating compartment 3 and the vegetable compartment 4 are provided with upper opening containers 3A and 4A. The vegetable compartment 4 and the freezer compartment 4 are closed by openable heat insulating doors 10 and 13, respectively. Further, the ice making chamber 5 is also openably and closably closed by a drawer type heat insulating door 11 having a container with an upper surface opening, and the select chamber 6 is also openably and closably closed by a similar drawer type heat insulating door 12. Further, the ice making chamber 5 is provided with an automatic ice making machine (not shown).

A partition plate 16 and an evaporator front plate 17 are provided from the back of the ice making chamber 5 and the select chamber 6 to the upper back of the freezing chamber 7.
Is divided into front and rear by the cooling chamber 1 on the rear side of the evaporator front plate 17.
8 are divided and formed, and a freezer evaporator 19 is provided in the cooling chamber 18. This freezer evaporator 19
A blower 20 for the freezer compartment is provided on the upper side of, and a drain receiver 21 is formed on the lower side of the evaporator 19 for the freezer compartment.

An ice making chamber discharge port, a select chamber discharge port, etc. are formed in the upper portion of the partition plate 16, a freezing chamber discharge port 7A is formed in the substantially central portion, and the lower portion side of the partition plate 16 is formed. The freezing room suction port 7B is formed. A motor damper (not shown) that opens and closes the flow path based on the temperature of the select chamber 6 is attached to the select chamber discharge port (not shown).

On the other hand, a rear heat insulating material 22 is attached to the inner part of the refrigerating compartment 3 at a distance from the rear surface of the inner box, and the rear heat insulating material 22 and the inner box 2 define a cooling chamber 23. A refrigerator compartment evaporator 24 is provided in the cooling room 23, and a refrigerator compartment fan 25 is mounted on the refrigerator compartment evaporator 24.
Is attached and a communication passage 26 is provided.

In the evaporator 19 for the freezer compartment, as shown in FIGS. 3 to 5, a large number of heat exchange fins 28 are arranged in the refrigerant pipe 27 at predetermined intervals in the length direction of the pipe. The heat exchanging fins 28 include first heat exchanging fins 28A having a large fin pitch, and fins having a small fin pitch including the first heat exchanging fins 28A and the second heat exchanging fins 28B. .

The freezer compartment evaporator 19 includes guide portions 29A and 2A which form a freezer compartment inlet 7B for the space of the freezer compartment 7.
9B and a wall portion 30 in contact with the evaporator front plate 17
The refrigerant pipe 27 and the heat exchanging fins 28 are arranged between the wall portion 31 and the wall portion 31 that is in contact with the heat insulating box 2 that forms the back surface of the inside of the refrigerator. A cold air guide plate 32 and a drain water dropping prevention roof 33 are provided below the refrigerant pipes 27 and the heat exchange fins 28, and the drain water dropping prevention roof 33 is provided.
A glass tube heater 34 is attached below the.

The evaporator 19 for the freezer compartment is provided with a capillary tube 35 on the side for supplying the refrigerant to the evaporator 19 for the freezer compartment.
And a header 36 is connected to the refrigerant outlet side of the freezer compartment evaporator 19, and the capillary tube 35 and the header 36 are respectively connected to the compressor 26A in the machine room. .

The refrigerant compressed by the compressor 26A is made to flow into the refrigerant pipe 27 in the evaporator 19 via the capillary tube 35. As shown in FIG. 4, on the front side, the refrigerant pipe 27 is horizontally extended, then curved downward (curve 27A) from the upper side, extended horizontally, and then downward again from the upper side. Curved (curve 27
B) and is extended in the horizontal direction. Thereafter, as shown in FIG. 5, the lowermost refrigerant pipe 27 is bent from the front side to the rear side (curve 27C) and horizontally extended, and then bent upward from the lower side to the horizontal direction. After being extended, it is curved (curve 27D) from the lower side to the upper side again, and is extended in the horizontal direction.

Similarly, on the rear side, the refrigerant pipe 27 is curved from the front side to the rear side, is horizontally extended, and is then curved from the upper side to the lower side (curve 27E).
After being extended in the horizontal direction, it is curved downward from above again and extended in the horizontal direction. After that, the lowermost refrigerant pipe 27 is curved backward (curve 27F) and horizontally extended, then curved upward from below, horizontally extended, and then upward again from below. Curved (curve 27
G), and is extended in the horizontal direction and connected to the header 36.

In the freezing evaporator 19, the refrigerant pipe 27 is used.
The first heat exchange fin 28A having a large pitch is attached to the refrigerant pipe 27 (rear side) having the curves 27E, 27F, and 27G.
The pitch is made small by A and the second heat exchange fins 28B (shown by broken lines in the figure), and the rear refrigerant pipe 2
The pitch of the heat exchange fins 28 in FIG. 7 is about 1 / the pitch of the heat exchange fins 28 in the refrigerant pipe 27 on the front side.
It is 2.

Next, when the compressor 26A constituting the refrigerant circuit of the refrigeration cycle in the machine room is operated, the blowers 20, 2 are blown.
5, the refrigerant discharged from the compressor 26A flows into the refrigerant pipe 27 in the evaporator 19 via the capillary tube 35. In the refrigerant pipe 27, the return cold air flowing in from the freezer compartment suction port 7B is cooled by the refrigerant pipe 27 and the heat exchange fins 28, and the refrigerant in the refrigerant pipe 27 is returned to the compressor 26A via the header 36. Further, the cool air obtained in the evaporator 24 flows into the vegetable compartment 4 side from the opening 15 through the blower 25 as shown by the arrow X, and is then introduced into the cooling compartment 23 to be cooled.

In FIG. 6, the heat exchange fins 2 are attached to the refrigerant pipe 27.
8 shows the relationship between the dryness and the heat transfer coefficient in a pipe in the case of an evaporator in which 8 is evenly attached with a pitch. As is clear from FIG.
The heat transfer coefficient in the pipe at the outlet of the refrigerant pipe on the header 36 side is about 20 to more than the inlet of the refrigerant pipe on the side of the capillary tube 35.
It is about 30% higher. Therefore, the header 36
On the refrigerant pipe outlet side of the side, the heat exchange efficiency of the evaporator 19 can be increased by reducing the pitch of the heat exchange fins.

Further, in the present invention, the region where the pitch of the heat exchange fins in the refrigerant pipe is reduced is not limited to the region of the heat exchange fins on the rear side described above, and the cool air returned from below the evaporator is returned to above. In the refrigerator to be passed, it is also possible to set it as a region where the amount of cold air passing through the evaporator is large. FIG. 7 shows another embodiment of the evaporator of the present invention,
Due to the length and installation angle of the cold air guide plate 12, the cold air passing upward from below the evaporator 19 is unevenly distributed. In the figure, the arrow portion indicates the center of the flow of cold air, and in this case, the area indicated by the broken line has a larger amount of cold air passing than the other areas, and the pitch of the heat exchange fins in this area is in other areas. It is smaller than the pitch of the heat exchange fins. In a refrigerator equipped with this evaporator, the pitch of the heat exchange fins is made smaller in a region with a large amount of cold air, and the heat exchange efficiency is increased in a region with a large amount of cold air, so that the heat exchange efficiency of the entire evaporator is improved. You can

In the refrigerator having the above-described configuration, the cooling efficiency is good even if the cool air is not uniformly returned to the evaporator. Therefore, it is not necessary to design the evaporator of the refrigerator so that the cool air returns uniformly, and the design constraint is greatly relaxed. In addition, the refrigerator of the illustrated form includes two evaporators, a refrigerator compartment temperature zone chamber evaporator and a freezing temperature zone chamber evaporator,
The evaporator according to the present invention is adopted as an evaporator for a temperature zone chamber for freezing, which has a vertical restriction. This is superior in the following points to a refrigerator in which all temperature zone chambers are cooled by one evaporator. That is, in a refrigerator that cools with a single evaporator, the cold air containing water that has passed through the refrigerating compartment and the vegetable compartment also returns to the evaporator in the present invention, so that the amount of frost increases and the fin pitch becomes dense. There is a fear of clogging. Therefore, it is necessary to take measures against this clogging. On the other hand, in the refrigerator of the illustrated form, since the cold air having a small amount of water that has passed through the freezing room is returned to the evaporator according to the present invention, the occurrence of clogging due to frost is a problem even in the dense fin pitch portion. Not so much.

The pitch of the heat exchange fins 28 on the rear side is
It is necessary to make it smaller than the pitch of the heat exchange fins 28 in the front side refrigerant pipe 27, but if the pitch of the heat exchange fins 28 in the rear side refrigerant pipe 27 is made too small, pressure loss in the evaporator 19 will occur. Therefore, in consideration of the overall heat exchange efficiency, the pitch of the heat exchange fins 28 in the rear side refrigerant pipe 27 /
The pitch of the heat exchange fins 28 in the refrigerant pipe 27 on the front side is preferably 1 / 1.2 to 1/5, more preferably 1/2 to 1/3. Further, the relationship between the pitch of the heat exchange fins in the region where the amount of cold air is large and the pitch of the heat exchange fins in the region where the amount of cold air is small is also as described above.

[0030]

According to the invention as set forth in claim 1, in a refrigerator provided with an evaporator in which a plurality of heat exchanging fins are mounted at intervals in a length direction of a refrigerant pipe, a refrigerant inflow side of the evaporator is provided. The heat exchange fins in the refrigerant pipe are arranged with a large pitch, and the heat exchange fins in the refrigerant pipe on the refrigerant outlet side of the evaporator are arranged with a small pitch. Side heat transfer coefficient is high, and the pitch of the heat exchange fins on the refrigerant outlet side of the evaporator is reduced to improve the heat exchange efficiency in this area.As a result, the evaporator volume can be reduced and the vegetable compartment, etc. It is possible to secure the volume of the device and reduce the power consumption.

According to a second aspect of the present invention, in addition to the structure of the above-mentioned invention, a refrigerating evaporator for a refrigerating temperature zone chamber and a freezing evaporator for a freezing temperature zone chamber are provided. The pitch of the heat exchanging fins in the refrigerant pipe on the refrigerant inflow side of the refrigerating evaporator for the temperature zone chamber is arranged to be large, and the pitch of the heat exchanging fins in the refrigerant pipe on the refrigerant outlet side of the refrigerating evaporator is arranged. The heat transfer coefficient in the tube on the refrigerant outlet side of the refrigerating evaporator for the refrigerating temperature zone chamber is high, and the refrigerant outlet of the refrigerating evaporator for the refrigerating temperature zone chamber is high. As a result of reducing the pitch of the heat exchange fins on the side to improve the heat exchange efficiency in this region, the volume of the refrigerating evaporator can be reduced and the power consumption can be reduced. .

According to the third aspect of the present invention, an evaporator is provided in which a plurality of heat exchange fins are attached at intervals in the lengthwise direction of the refrigerant pipe, and cool air is returned from below the evaporator to above. In the refrigerator to be passed, the region with a large amount of cold air passing through the evaporator has a smaller pitch of the heat exchange fins than the region with a small amount of cold air passing through the evaporator. Since the pitch of the heat exchange fins is made small in the large area, the heat exchange efficiency can be made high in the area where the amount of cold air is large, and the heat exchange efficiency of the entire evaporator can be made high. Efficiency can be increased.

According to a fourth aspect of the present invention, in addition to the configuration of the above-mentioned invention, an evaporator in which a plurality of heat exchange fins are mounted at intervals in the length direction of the refrigerant pipe is provided, and the evaporator is provided. In a refrigerator that allows return cold air to pass upward from below, the amount of cold air passing through the evaporator is biased rearward from the front, and the refrigerant pipe is meandered so that the refrigerant flows rearward from the front, and the front side Since the pitch of the heat exchange fins is increased and the pitch of the heat exchange fins on the rear side is decreased, the rear evaporator has a large amount of cool air and a high heat transfer coefficient in the pipe. The pitch of the heat exchange fins of the evaporator is reduced to improve the heat exchange efficiency in this region, and the volume of the evaporator can be further reduced.

According to the fifth aspect of the present invention, a refrigerating evaporator for the refrigerating temperature zone chamber and a freezing evaporator for the freezing temperature zone chamber are provided, and the evaporator is for the freezing temperature zone. Since it is a room refrigeration evaporator, the pitch of the heat exchange fins of the refrigeration evaporator for the refrigeration temperature zone room is set in a predetermined relationship, and the return cold air flowing into the evaporator is efficient. Is cooled to
This cold air is supplied to the freezing temperature zone chamber.

According to the sixth aspect of the present invention, the machine room is provided in the lower rear part, and the temperature zone chamber for freezing is provided in the lowest stage.
A cooling chamber provided with the evaporator is provided behind the freezing temperature zone chamber. Since the cooling chamber does not extend to the refrigeration temperature zone chamber, the cooling chamber is provided behind the freezing temperature zone chamber, and In the cooling chamber equipped with a heat exchanger, even if a non-uniform flow of the return cool air occurs, the rear evaporator has a large amount of cool air and a high heat transfer coefficient in the pipe, and the pitch of the heat exchange fins of the evaporator in this region is high. Is made smaller to improve the heat exchange efficiency in this region, and the temperature zone for refrigeration does not become too cold.

[Brief description of drawings]

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

FIG. 2 is a vertical side view of the refrigerator of the present invention.

FIG. 3 is a perspective view of a main part of an evaporator in the refrigerator of the present invention.

FIG. 4 is a front view of the essential parts showing an example of the arrangement of the refrigerant pipes and heat exchange fins of the evaporator in the refrigerator of the present invention.

FIG. 5 is a side view showing an arrangement example of refrigerant pipes and heat exchange fins of an evaporator in the refrigerator of the present invention.

FIG. 6 is a graph showing heat exchange efficiency in a tube in the evaporator of the refrigerator of the present invention.

FIG. 7 is an explanatory diagram showing another arrangement example of the refrigerant pipes and heat exchange fins of the evaporator in the refrigerator of the present invention.

[Explanation of symbols]

1 refrigerator 3 refrigerating room 4 vegetable room 7 Freezer 19 Freezer evaporator 20 Blower for freezer 24 Refrigerator Evaporator 25 Chiller blower 26A compressor 27 Refrigerant piping 28A Heat exchange fin 28B heat exchange fin 30 walls 31 wall 32 Cold air guide plate 33 Drain Water dripping prevention roof 34 Glass tube heater 35 capillary tubes 36 header

Continued front page    (72) Inventor Nishi Hiroshi             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd.

Claims (6)

[Claims] 1. A refrigerator provided with an evaporator in which a plurality of heat exchange fins are attached at intervals in the length direction of the refrigerant pipe, wherein the pitch of the heat exchange fins in the refrigerant pipe on the refrigerant inflow side of the evaporator. The refrigerator is characterized in that the heat exchange fins in the refrigerant pipe on the refrigerant outlet side of the evaporator are arranged with a small pitch. 2. A refrigerating evaporator for a refrigerating temperature zone chamber and a freezing evaporator for a refrigerating temperature zone chamber, wherein the refrigerant on the refrigerant inflow side of the refrigerating evaporator for the refrigerating temperature zone chamber A refrigerator characterized in that the heat exchange fins in the pipe are arranged with a large pitch, and the heat exchange fins in the refrigerant pipe on the refrigerant outlet side of the refrigerating evaporator are arranged with a small pitch. 3. A refrigerator comprising an evaporator having a plurality of heat exchange fins mounted at intervals in the length direction of a refrigerant pipe, wherein the cooler is returned from the lower side of the evaporator and the cool air is passed upward. A refrigerator characterized in that a pitch of the heat exchange fins is made smaller in an area having a large amount of cold air passing therethrough than in an area having a small amount of cold air passing through the evaporator. 4. A refrigerator having an evaporator, in which a plurality of heat exchange fins are mounted at intervals in the length direction of a refrigerant pipe, and wherein cool air is returned upward from below the evaporator, and inside the evaporator, The amount of cold air passing through is biased rearward from the front, and the refrigerant pipe is meandered so that the refrigerant flows rearward from the front, and the pitch of the heat exchange fins on the front side is increased to increase the heat exchange on the rear side. A refrigerator characterized in that the fin pitch is reduced. 5. The refrigerating evaporator for a refrigerating temperature zone chamber, comprising a refrigerating evaporator for a refrigerating temperature zone chamber and a freezing evaporator for a freezing temperature zone chamber, according to claim 4. The refrigerator according to claim 4, wherein the refrigerator is an evaporator. 6. A machine room is provided at the lower rear part, and a freezing temperature zone chamber is provided at the lowermost stage, and the evaporator according to claim 1 is provided behind this freezing temperature zone chamber. The refrigerator according to claim 1, further comprising: a cooling chamber provided, the cooling chamber not extending to the refrigerating temperature zone chamber.