JPS60181568A - 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 having a plurality of fin-and-tube coolers, and in particular to its fin pitch and heat medium temperature.

Structure of a conventional example and its problems As shown in FIGS. 1 and 2, a conventional refrigeration system is provided with a cooling chamber 2 that forms a circulation path for ventilation air flow within a heat-insulating partition wall 1 of a refrigerator. A cooler 3 and a fan 4 are arranged within the chamber 2. The cooler 3 has a plurality of fins 5
, 6' and the fins 6.6' are inserted into the refrigerant pipe attachment holes 6 formed in the fins 6.6' and then expanded to form the fins 6.6.
It consists of a refrigerant pipe 7 in close contact with the fin 6.6', and an end plate 8 fitted from both sides.
is divided into two parts, fins 5 on the ventilation side and fins 6' on the leeward side, and the fin pitch on the windward side is larger than the fin pitch on the leeward side. This means that the temperature of the heat medium flowing in the refrigerant pipe 7 is below 0°C, and the ventilation air temperature and wet bulb temperature are also 0°C.
If the temperature is below °C, frost will form on the cooler 3. At this time, frost will develop on the cooler 3 from the upstream side of the ventilation wind and gradually progress to the leeward side. This makes it easier for the windward side of the fins to become clogged due to frost formation, forcing the fin pitch □ on the windward side to be increased. Therefore, the heat transfer surface area of the cooler 3 is reduced by the increase in the fin pitch on the upper side of the ventilation, and in order to secure the heat transfer surface area, that is, the cooling capacity, the entire cooler must be made larger. It had drawbacks. In addition, some of this type of refrigeration equipment has a bypass air path that bypasses a part of the windward side of the cooler in the ventilation air circulation path in the cooling room, but this also depends on the size of the cooler and the heat transfer surface area. Regardless of the above, it is clear that the frost on the cooler is uniform to some extent and the time until clogging due to frost buildup as a whole can be slightly lengthened. It has the same drawbacks.

Purpose of the Invention Therefore, the present invention aims to maintain cooling capacity by increasing the time until clogging due to frost formation without increasing the fin pitch on the upper side of the ventilation wind, that is, without reducing the heat transfer surface area. purpose.

Structure of the Invention In order to achieve this object, the present invention improves heat transfer by increasing the temperature level of the heat medium in the upstream cooler and reducing the fin pitch of the cooler compared to the downwind cooler. The external heat surface area (cooling capacity) is increased, the time until clogging due to frost formation is increased, and the cooling capacity can be maintained.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In FIGS. 3 and 4, an embodiment of a refrigerator is shown, and the same parts as in the conventional example are designated by the same numbers.

A cooling chamber 2 forming a circulation path for ventilation air flow is provided within the heat insulating partition wall 1, and a first cooler 1o, a second cooler 11, and a fan 4 are arranged in the cooling chamber 2 in the direction of ventilation flow. .

The first cooler 1o and the second cooler 11 are each inserted through a plurality of fins 12.13 and refrigerant pipe attachment holes 14.15 drilled in these ins 12.13, and are then expanded. Refrigerant pipe 16 in close contact with fins 12.13.
17 and the en)"F L/-) 1 inserted from both sides
8.19. The fin pitch of the first cooler 1o placed on the upstream side of this ventilation is smaller than the fin pitch of the second cooler 11 placed on the leeward side, and the refrigerant pipe 16 of the first cooler 1o The refrigeration system is controlled and configured to operate separately so that the temperature level of the heat medium flowing therein is higher than that in the refrigerant pipe 17 of the second cooler 11.

In the above configuration, the fin pitch is made small in the first cooler 1° on the upper side of the ventilation wind, and since a large number of fins 12 are provided, the cooling capacity is improved within the same external dimensions due to the large heat transfer surface area. .

Next, the frost formation under conditions where frost formation occurs (heating medium temperature is 0''C or less, ventilation air wet bulb temperature is also 0''C or less) will be described. First, frost formation starts from the first cooler 1o on the upstream side of the ventilation wind, and the frost gradually grows and the thickness of the frost layer increases.
Because of this temperature difference, the frost adhering to the first cooler 10, which has a higher temperature level, moves by sublimation to the second cooler 11, which has a lower temperature level, on the leeward side. The frost formation on the first cooler 1o and the second cooler 11 becomes uniform. Further, since the first cooler 1° has a larger heat transfer outer surface area as described above, the frost layer thickness becomes smaller for the same amount of frost formation, and clogging due to N frost becomes less likely to occur.

Therefore, since the fin pitch of the first cooler 10 can be reduced, the heat transfer outer surface can be increased, that is, the cooling capacity can be increased. The frost adhering to the first cooler 1o gradually sublimates to the second cooler 11, and the frost adheres to the first cooler 1o.
, No. 11, the frost formation is uniform, and the heat transfer outer surface area is large, so the frost layer thickness is small, and clogging due to frost occurs.

It is less likely to stiffen, the time until clogging due to frosting can be significantly extended, and the cooling capacity can be maintained even if frosting progresses.

Effects of the Invention As is clear from the above explanation, the present invention has the advantage of increasing the temperature level of the heating medium and reducing the fin pitch of the cooler on the upstream side of the draft compared to the cooler on the leeward side. , by increasing the heat transfer outer surface area, that is, the cooling capacity, and by making the frost formation uniform, it is possible to lengthen the time until clogging due to frost formation, and to maintain the cooling capacity even when frost formation progresses. This has the effect of being able to do the same.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the main parts of a refrigerator in a conventional refrigeration system, Fig. 2 is a perspective view of the same cooler, Fig. 3 is a sectional view of the main parts of a refrigerator in an embodiment of the refrigeration system of the present invention, and Fig. 4 is a sectional view of the main parts of a refrigerator in a conventional refrigeration system. It is a perspective view of the same cooler. 1o...First cooler, 11...Second cooler, 12.13...Fin, 16.17...
...Refrigerant pipe. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure! Figure 2

Claims (1)

[Claims] A plurality of fin-and-cheap type coolers are arranged in series in the circulation path of the ventilation air flow, and the cooler on the windward side has a higher temperature level of the heat medium than the cooler on the leeward side, and its fin pitch is increased. Refrigeration equipment made smaller.