JPH0218448Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field This invention relates to a refrigeration system used in air conditioners and cooling equipment.

(b) Prior art The evaporator is formed by a multi-pipe heat exchanger consisting of a plurality of unit heat exchangers, and the unit heat exchanger has a resistance value adapted to the load of the unit heat exchanger on the refrigerant inlet side. A refrigeration system with selective connection of diverter tubes was put into practice in 1973.
This is disclosed in Publication No. 11499 and Publication No. 11500 of 1972. However, in these refrigeration systems, the refrigerant flow rate of low-load unit heat exchangers with poor heat exchange rate is throttled at the refrigerant inlet side to prevent the refrigerant from flowing out from the unit heat exchanger without being fully evaporated. The evaporation pressure of the unit heat exchanger has decreased, and combined with the poor heat exchange rate, the low-load unit heat exchanger has the disadvantage of being susceptible to frost formation.

(c) Purpose of the invention This invention provides a refrigeration system that prevents unevaporated refrigerant from flowing out of a low-load unit heat exchanger and prevents frost formation on the low-load unit heat exchanger as much as possible. It's about doing.

(d) Structure of the invention This invention divides the evaporator into a plurality of unit heat exchangers, and installs a flow divider and a flow pipe to separate the refrigerant that has been depressurized by a pressure reducing element into each of these unit heat exchangers. placing an exchanger in the fluid path;
The refrigerant outlet pipe of the unit heat exchanger located in a place where the fluid flow rate is low in this passage is equipped with a constriction part with a small pipe diameter.The constriction part reduces the amount of refrigerant passing through the unit heat exchanger with a low load. In addition to preventing the refrigerant from flowing out from this unit heat exchanger without being fully evaporated, the unit heat exchanger is also designed to have the same pressure as other high-load unit heat exchangers without throttle parts. By introducing a liquid refrigerant, the evaporation pressure of the low-load unit heat exchanger is maintained high to prevent frost formation.

(E) Example An example of the present invention will be explained based on the drawings. In the refrigerant circuit diagram in Fig. 1, 1 is an outdoor unit incorporating a compressor 2 and a condenser 3, and 4 is an expansion valve or a capillary reach tube. A pressure reducing element 5 consisting of
, a flow divider 6, and flow divider pipes 7a, 7 of this flow divider.
two evaporators 8a connected to b, 7c, 7d;
8b, and refrigerant outlet pipes 9a, 9b, 9 of this evaporator.
This is an indoor unit that incorporates a collecting pipe 10 connected to air conditioners 1 and 9d, and a separate air conditioner is constructed by connecting both units 1 and 4 with inter-unit piping 11 and 12. .

The above-mentioned evaporators 8a and 8b each have a branch pipe 7.
a, 7b, 7c, 7d and refrigerant outlet pipes 9a, 9b,
A plurality of unit heat exchangers 1 connected to 9c and 9d
3a, 13b, 13c, and 13d, and this evaporator 8
As shown in the sectional view of the indoor unit 4 of the ceiling-mounted type shown in FIG. It is designed to exchange heat with indoor air. The indoor air that has been cooled by heat exchange is blown into the room through the left and right ducts 16, 17 and from the outlets 18, 19, thereby cooling the room. 8
The indoor air flow sent to b is Sirotskov fan 15
is rotated clockwise in FIG. 2, so it tilts to the right as shown by the solid arrow, and the unit heat exchanger 13d in the lower half of one evaporator 8b is compared to the unit heat exchanger 13c in the upper half. The amount of ventilation is smaller than that of the unit heat exchangers 13a and 13b of the other evaporator 8a.

As shown in FIG. 3, reference numeral 20 denotes a constricted part with a small pipe diameter provided in the refrigerant outlet pipe 9d of the low-load unit heat exchanger 13d with a small ventilation volume. This unit heat exchanger 13d reduces the amount of liquid refrigerant flowing through the unit heat exchanger 13d while remaining unevaporated.
The liquid refrigerant is transferred to the low-load unit heat exchanger 13d with the same pressure as the other high-load unit heat exchangers 13a, 13b, and 13c while trying to prevent it from flowing out from the low-load unit heat exchanger 13d.
By introducing the unit heat exchanger 13d, the evaporation pressure of the unit heat exchanger 13d is maintained high and frost formation is prevented. The explanation of FIG. 3 will be omitted by assigning the same reference numerals as those of FIGS. 1 and 2.

(f) Effects of the invention According to this invention, a constriction part with a small pipe diameter is provided in the refrigerant outlet pipe of the low-load unit heat exchanger among the plurality of unit heat exchangers that make up the evaporator. By reducing the amount of refrigerant passing through the low-load unit heat exchanger at the throttle section, it is possible to prevent the refrigerant from flowing out of the unit heat exchanger without evaporation and returning to the compressor. By introducing liquid refrigerant into the heat exchanger with the same pressure as other high-load unit heat exchangers, the evaporation pressure of the low-load unit heat exchangers is maintained high and frost formation is prevented. Can be done.

[Brief explanation of the drawing]

FIG. 1 is a refrigerant circuit diagram of the present device, FIG. 2 is a sectional view of an indoor unit in the present device, and FIG. 3 is a perspective view of the main parts of the present device. 2... Compressor, 3... Condenser, 5... Pressure reducing element, 8a, 8b... Evaporator, 9a, 9b, 9c,
9d...Refrigerant outlet pipe, 13a, 13b, 13c,
13d... Unit heat exchanger, 20... Throttle section.

Claims (1)

[Scope of utility model registration request] In a refrigerant circuit formed by sequentially connecting a compressor, a condenser, a pressure reducing element, and an evaporator, the evaporator is divided into a plurality of unit heat exchangers, and the refrigerant depressurized by the pressure reducing element is transferred to each of these unit heat exchangers. A flow divider and a flow pipe are provided for dividing the flow, and these unit heat exchangers are placed in a fluid passage. A refrigeration device characterized by having a small constriction section.