JPH1078270A - Refrigerant blow-off sound preventing structure of capillary tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an occurrence of a refrigerant blow-off sound by forming an enlarged tube portion at a connecting end of a capillary tube connected with an evaporator. SOLUTION: A capillary tube 10 is made of a copper alloy tube material and has its front end formed in an enlarged tube portion 10a. The capillary tube 10 has its proximal end connected with a liquid receiver. At a connecting portion where the capillary tube 10 and an inlet connecting tube 4 of an evaporator are connected with each other, a liquefied refrigerant which flows through the capillary tube 10 passes through the enlarged tube portion 10a of the capillary tube 10 and is blown off from a distal end opening 11 thereof toward an inside of an enlarged diameter portion 4b of the inlet connecting tube 4. With such a blow-off operation, since the blow-off velocity and blow-off pressure of the refrigerant from the distal end opening 11 of the capillary tube 10 can be reduced compared to those of conventional capillary tubes, the occurrence of the refrigerant blow-off sound can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration cycle, and more particularly, to a structure for preventing noise from being discharged from a capillary tube to an evaporator in a refrigerant circuit of a refrigerator.

[0002]

2. Description of the Related Art In a refrigerator circuit of a refrigerator, a compressor, a condenser, an evaporator and the like are connected by a refrigerant flow pipe. For example, in a conventional refrigerator, as shown in FIG. 4, an inlet connection pipe of an evaporator (2) is provided. In the case of (4), one end of the capillary tube (30) is connected to the reduced diameter portion (4a) at one end in a state where the two ends are almost completely inserted.

[0003]

However, the inside diameter of the capillary tube (30) is very small, less than 1 mm, and is about 3.5 to 6 mm from the tip opening (31).
Inlet connecting pipe (4) of evaporator (2) with front and rear inner diameter
When the refrigerant is rapidly discharged into the large-diameter portion (4b), a large discharge noise is generated at that time.

An object of the present invention is to solve the above problems.

[0005]

According to a first aspect of the present invention, a refrigerant discharge sound preventing structure for a capillary tube is provided in which a connection end of the capillary tube with an evaporator is an expanded portion.

If the end of the capillary tube communicating with the evaporator is formed as an expanded portion, the refrigerant is discharged through the expanded portion into the inlet connecting pipe or the refrigerant passage of the evaporator. The discharge speed and pressure of the refrigerant from the refrigerant decrease. This makes it possible to prevent the generation of the refrigerant discharge noise.

Here, the inside diameter and length of the expanded portion formed in the capillary tube are determined by the speed and pressure of the refrigerant flowing through the tube, the inside diameter of the inlet connecting pipe of the evaporator or the portion of the refrigerant passage where the refrigerant is discharged. (Cross-sectional area) or the like.

In the second aspect of the present invention, there is provided a refrigerant discharge sound preventing structure for a capillary tube, wherein a refrigerant discharge through-hole or a notch is formed in a pipe wall at an end of the capillary tube connected to an evaporator. One is provided.

As described above, if a through hole or a notch is provided in the tube wall at the end of the capillary tube communicating with the evaporator so that the refrigerant is discharged from the same portion, the total opening area of the refrigerant discharge port is increased. Therefore, the discharge speed and pressure of the refrigerant from each of the tube opening, the through hole, and the notch decrease. This makes it possible to prevent the generation of the refrigerant discharge noise.

The coolant discharge through-hole or notch may be at least one, but may be plural. The size of the through hole or notch (opening area) depends on the number of these, the speed and pressure of the refrigerant flowing through the capillary tube,
It is appropriately set according to the inner diameter (cross-sectional area) of the portion of the evaporator at which the refrigerant is discharged in the inlet connection pipe or the refrigerant passage.

[0011]

Next, preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the first aspect of the present invention, and a capillary tube in a refrigerator.
The connecting portion between (10) and the inlet connecting pipe (4) of the evaporator is shown.

The capillary tube (10) has an inner diameter of 0.8 m
m of a copper alloy tube material, and the tip portion is an expanded portion (10a) having an inner diameter of 1.5 mm. Expanding section (10
The length of a) is about 40 mm including the tapered portion.
For expanding the capillary tube (10), a known pipe expanding method may be used, and there is no particular limitation. The base end of the capillary tube (10) is connected to a liquid receiver.

The inlet connecting pipe (4) of the evaporator is, for example, an aluminum-copper connecting pipe having an inner diameter of 3.85 mm.
At the connection end of the capillary tube (10) in (4), a constricted portion (4a) is provided by spinning or the like, and the inner peripheral surface of the constricted portion (4a) expands the capillary tube (10). It is almost close to the part (10a). Inlet connection pipe
The length of the constricted portion (4a) of (4) is shorter than the expanded portion (10a) of the capillary tube (10),
The opening (11) at the tip of (10) is the constricted section of the inlet connection pipe (4).
It is located in the large diameter portion (4b) adjacent to (4a). The peripheral portion of the opening of the inlet connecting pipe (4) on the side of the contracted tube (4a) is welded to the expanded tube (10a) of the capillary tube (10).

At the connection between the capillary tube (10) and the inlet connection pipe (4) of the evaporator, the liquefied refrigerant flowing through the capillary tube (10) passes through the expanded portion (10a) of the capillary tube (10). The water is discharged from the opening (11) into the large-diameter portion (4b) of the inlet connection pipe (4). At this time, the discharge speed and pressure of the refrigerant from the tip opening (11) of the capillary tube (10) are significantly reduced as compared with the case of the conventional capillary tube having no expanded portion (10a). Does not occur.

FIG. 2 shows another embodiment of the first aspect of the present invention, in which a capillary tube (10) has an opening (11) at the tip end thereof which has a contracted tube portion (4a) in an inlet connecting tube (4). Is the same as the embodiment shown in FIG. 1 except that it is located in the middle of the length.

The capillary tube (1) shown in FIG.
At the connection between the evaporator (0) and the inlet connection pipe (4) of the evaporator, the liquefied refrigerant flowing through the capillary tube (10) is:
The liquid is discharged from the opening (11) of the capillary tube (10) through the expanded portion (10a) into the contracted portion (4b) of the inlet connecting pipe (4). At this time, the discharge speed and pressure of the refrigerant from the tip opening (11) of the capillary tube (10) are controlled by the expansion section (1).
0a) is greatly reduced as compared with the conventional capillary tube having no, and the cross-sectional area is increased stepwise (four steps) from the capillary tube (10) toward the inlet connection pipe (4). FIG. 3, which shows no refrigerant discharge noise, shows an embodiment of the invention according to claim 2 and shows a connection portion between a capillary tube (20) and an inlet connection pipe (4) of an evaporator in a refrigerator. ing.

The capillary tube (20) has an inner diameter of 0.8 m
m of a copper alloy tube. In the tube wall near the tip opening (21) of the capillary tube (20), two coolant discharge through holes (22) having a diameter of 0.6 mm are formed on the same diameter. The base end of the capillary tube (20) is connected to a liquid receiver. Instead of the through-hole (22), one or more U-shaped or V-shaped coolant discharge notches (23) may be formed as shown by a chain line in FIG.

The inlet connecting pipe (4) of the evaporator is, for example, an aluminum-copper connecting pipe having an inner diameter of 3.85 mm. The connecting end of the pipe (4) with the capillary tube (20) is formed by spinning or the like. A reduced tube portion (4a) is provided, and an inner peripheral surface of the reduced tube portion (4a) is a capillary tube (20).
It is almost in close contact with the tip of. Capillary tube (20) tip opening (21) and coolant discharge through hole (22)
Is located in the large diameter portion (4b) adjacent to the contracted tube portion (4a) in the inlet connection pipe (4). The peripheral portion of the opening of the inlet connecting pipe (4) on the side of the contracted pipe (4a) is welded to the tip of the capillary tube (20).

At the connecting portion between the capillary tube (20) and the inlet connection pipe (4) of the evaporator, the liquefied refrigerant flowing through the capillary tube (20) passes through the opening (21) at the tip end of the capillary tube (20) and the opening thereof. The refrigerant is discharged from the two coolant discharge through holes (22) formed in the nearby pipe wall into the large-diameter portion (4b) of the inlet connection pipe (4). At this time, the discharge speed and pressure of the refrigerant from the tip opening (21) and the through hole (22) of the capillary tube (20) are compared with those from the tip opening of the capillary tube without the through hole (22). Since it is greatly reduced, no refrigerant discharge noise is generated.

[0021]

According to the present invention, it is possible to easily and reliably prevent the refrigerant discharge noise from the capillary tube in a refrigerator or the like.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a connecting portion between a capillary tube and an inlet connecting pipe of an evaporator according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a connection portion between a capillary tube and an inlet connection pipe of an evaporator according to another embodiment of the invention described in claim 1;

FIG. 3 is a front view of a connecting portion between a capillary tube and an inlet connecting pipe of an evaporator, showing one embodiment of the invention described in claim 2;

FIG. 4 is a longitudinal sectional view of a connection portion between a capillary tube and an inlet connection pipe of an evaporator, showing a conventional technique.

[Explanation of symbols]

 (2) Evaporator (4) Inlet connecting pipe (10) Capillary tube (10a) Expanding section (20) Capillary tube (22) Coolant discharge through hole (23) Notch for refrigerant discharge

Claims (2)

[Claims] 1. A refrigerant discharge sound preventing structure for a capillary tube, wherein a connection end of the capillary tube with an evaporator is an expanded portion. 2. A refrigerant discharge sound preventing structure for a capillary tube, wherein either one of a refrigerant discharge through hole and the notch is provided in a tube wall of the capillary tube at a communication end portion with the evaporator.