JP2001183022A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator to be simply manufactured in a manner to prevent the occurrence of leakage, in the refrigerator having a shell container in which a lock ring is used. SOLUTION: A refrigerator 10 is constituted such that a metal seal 17 formed of an Sn-Pb alloy where a content of Sn is 25-30 wt.% is used between a crank case 11 and hermetic seal 12, which are joined together by a lock ring 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator whose outer shell is formed using a lock ring.

[0002]

2. Description of the Related Art An outer shell container (pressure container) of a refrigerator such as a Stirling refrigerator generally includes an outer shell container body having an opening, and a removable hermetic seal member for sealing the opening. Are joined. The joining of the hermetic seal member and the outer shell container body is usually performed by forming a flange on each of the hermetic seal member and the outer shell container body, and fastening the flanges with a plurality of bolts. .

[0003] Further, since there is no room for providing a flange at the joint portion (or to reduce the size of the refrigerator), a refrigerator is used in which a hermetic seal member and a shell body are joined by a lock ring. Is also known.

[0004]

In a refrigerator in which an outer shell container is formed using a flange, a plurality of bolts are tightened in a predetermined procedure at the time of manufacture (assembly) of the refrigerator, so that the hermetic seal member and the outer container are connected to each other. An even and appropriate load can be applied to the metal seal disposed between the shell container bodies. For this reason, this type of refrigerator can be relatively easily manufactured without leakage.

On the other hand, in a refrigerator in which the hermetic seal member and the outer shell container body are joined by a lock ring, a load is applied to the joint by one lock ring. It is difficult to manufacture without leaks (they would leak if not assembled by a skilled person).

It is an object of the present invention to provide a refrigerator having an outer shell container using a lock ring, which can be easily manufactured.

[0007]

Means for Solving the Problems As a result of diligent studies to solve the above problems, the present inventors have found that a metal member is provided between a case member having an opening, a lock ring, and a case member. When a refrigerator including a hermetic seal member that is joined to a case member by a lock ring and seals an opening of the case member with the seal sandwiched, Sn (tin) is contained as a metal seal. It has been found that a material made of a Sn—Pb (lead) alloy having a ratio in the range of 25 to 35% by weight may be used.

That is, according to the present invention, the refrigerator is not made of a conventionally used indium metal seal, but is made of Sn-Pb having a Sn content of 25 to 35% by weight.
It is configured using a metal seal made of an alloy.

In the refrigerator of the present invention, a Sn-containing metal seal having a Sn content of 25 to 35% by weight is used.
Any original shape (shape before assembly) can be used as long as it is made of a Pb alloy. However, it is desirable to use a metal seal formed in a ring shape, since the assembling operation becomes easy.

[0010]

Embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 shows a configuration of a refrigerator according to an embodiment of the present invention. FIG. 1A is a cross-sectional view of a portion of the refrigerator 10 according to the embodiment in which the lock ring 13 is used, and FIG. 1B is a diagram illustrating joining of the refrigerator 10 by the lock ring 13. It is an expanded sectional view of a part.

The refrigerator 10 according to the embodiment is a so-called crank-integrated Stirling refrigerator in which a displacer and a piston are reciprocated by a crank mechanism. As shown in FIG.
A crankcase 11 and a hermetic seal 12 joined by the above are provided. Further, the refrigerator 10 includes an O-ring 16 and a metal seal 17 for sealing between the crankcase 11 and the hermetic seal 12. In the refrigerator 10, a closed space (hereinafter, referred to as a motor housing space) formed by the crankcase 11, the hermetic seal 12, the metal seal 17, and the like is provided.
A stator 15 for driving a crank mechanism (not shown)
a and a motor 15 composed of a rotor 15b.

As shown in FIGS. 1A and 1B,
The lock ring 13 includes a hollow cylindrical portion whose inner surface is threaded, and a ring-shaped portion formed by reducing the inner diameter of one end of the portion.
The lock ring 13 is made of SUS304 and has a thread root diameter of 45 mm.

The crankcase 11 is a member that constitutes most of the outer shell container of the refrigerator 10, and is made of Al (aluminum).
It is composed of an alloy. A portion of the crankcase 11 forming a motor housing space (hereinafter, referred to as a motor housing portion) has a cylindrical shape. A screw having a shape corresponding to the screw cut on the inner surface of the lock ring 13 is cut on the outer surface of the motor housing. The inner surface of the motor accommodating portion has a structure including a cylindrical first seal surface 31 and a planar ring-shaped second seal surface 32 orthogonal to the first seal surface 31 (hereinafter referred to as a receiving structure). Is provided.

The first seal surface 31 is a surface that comes into contact with the O-ring 16 and the metal seal 17 when the refrigerator 10 is assembled. The second sealing surface 32 is a surface that comes into contact with the metal seal 17 when the refrigerator 10 is assembled. A groove 32a having a V-shaped cross section having a width of about 0.5 mm and a depth of about 0.2 mm is formed on the second sealing surface 32 so as to form a closed curve surrounding the motor housing space. I have.

The hermetic seal 12 includes a cylindrical portion provided with a flange near the lower end (the end on the side inserted into the crankcase 11), and a disk-shaped portion closing the upper end of the cylindrical portion. In addition, hermetic seal 1
2 is mainly composed of an FeNi (iron / nickel) alloy.

A current-introducing terminal 14 for a motor 15 is provided on a disc-shaped portion of the hermetic seal 12. The outer diameter of the cylindrical portion of the hermetic seal 12 is smaller than the inner diameter of the ring-shaped portion of the lock ring 13. The outer shape of the flange provided on the cylindrical portion of the hermetic seal 12 is larger than the inner diameter of the ring-shaped portion of the lock ring 13 and smaller than the inner diameter of the screw (female screw) provided on the lock ring 13. .

At the lower end of the cylindrical portion of the hermetic seal 12, a structure (hereinafter referred to as a plug-in structure) that is fitted with the receiving structure of the crankcase 11 is formed. The insertion structure of the hermetic seal 12 has a cylindrical shape in which a groove 21 for attaching the O-ring 16 is formed. In addition, a tapered surface 22 that is in contact with the metal seal 17 and functions as a seal surface is formed on the outer peripheral side of the distal end portion of the insertion structure.

As described above, the refrigerator 10 has the same configuration as the existing crank-integrated Stirling refrigerator using a lock ring. However, in a general Stirling refrigerator with a crank, an indium wire is used as the metal seal 17.
Here, a ring-shaped Sn—Pb alloy having a Sn content of 30% by weight is used as the metal seal 17.

The refrigerator 10 of the embodiment is manufactured (assembled) by the procedure shown in FIG.

That is, when the refrigerator 10 is manufactured, first, the refrigerator 10 is assembled until the lock ring 13 is lightly tightened (the lock ring 13 can be tightened) (step 1). Then, the refrigerator 10
Is placed in a drying oven (constant temperature bath) set at a predetermined temperature and left for a predetermined time (step 2).

In this step 2, the metal seal 1 sandwiched between the crankcase 11 and the hermetic seal 12 is used.
This is a step performed to make 7 more extensible. Therefore, it is desirable that the temperature (predetermined temperature) of the drying furnace in step 2 be as high as possible without causing deterioration of the components of the refrigerator 10 to be manufactured. In addition, the time (predetermined time) during which the temperature of the entire refrigerator (particularly, around the metal seal 17) placed in the drying furnace is reduced.
It is desirable to ensure that the temperature reaches the same temperature as the drying oven.

At the time of manufacturing the refrigerator 10 according to the embodiment,
The upper limit temperature at which the characteristics of the motor 15 do not deteriorate is about 70 ° C
Therefore, the temperature of the drying oven was set to 70 ° C.
Step 2 is performed with one hour, which is the time during which the entire temperature reliably reaches 70 ° C., as the predetermined time.

After the completion of the step 2, the refrigerator 1
Then, a predetermined load is applied to the refrigerator 10 heated to approximately a predetermined temperature (70 ° C.) by a press in a tightening direction (vertical direction in FIG. 1) by the lock ring 13 for a predetermined time. Leave to stand (step 3).

Step 3 is a step for forming a state in which the first seal surface 31, the second seal surface 32, and the tapered surface 22 are in good contact with the metal seal 17. Therefore, it is desirable that the predetermined load is set as large as possible without breaking the refrigerator 10. In addition, since the temperature of the refrigerator 10 at the time when the step 4 described later is performed is determined by the time (predetermined time) to be left, the predetermined time in the step 3 is such that the temperature of the refrigerator 10 is reduced to around room temperature. It is desirable to set the time to fall.

For this reason, when the refrigerator 10 is manufactured, a load of 160 kgf close to the upper limit load at which the buckling of the crankcase 11 does not occur is applied in the step 3. Then, the state where the load of 160 kgf is applied is maintained for one hour, which is the time when the temperature of the refrigerator 10 decreases to around room temperature.

After the completion of the step 3, the lock ring 13 is tightened with the load applied (step 4), and the application of the load is stopped to obtain the refrigerator 10. Note that the tightening torque of the lock ring 13 in the step 4 is preferably such that a load of about 160 kgf or more is applied to the metal seal 17 even after the load is stopped by the press. In the manufacture of No. 10, step 4 is performed at 1100 kgf · c
This is a step of tightening the lock ring 13 with a tightening torque of m.

It has been confirmed that all the refrigerators 10 manufactured so far by such a procedure have no leak. The test results of the refrigerator 10 manufactured by changing the composition of the metal seal 17 show that the Sn content is 2%.
Even if the metal seal 17 made of Sn or Pb alloy of 35% by weight is used, the refrigerator 1 always has no leak.
It has been confirmed that 0 can be obtained.

Further, even if a Sn—Pb alloy wire having a Sn content of 25 to 35% by weight is used as the metal seal 17,
It has also been confirmed that a refrigerator 10 having no leak can always be obtained. However, in this case, when assembling,
Since it is necessary to arrange the linear metal seal 17 so as to have a predetermined shape on the second seal surface 32, it is preferable to use a metal seal 17 formed in a ring shape.

[0030]

According to the present invention, since the refrigerator of the present invention is less likely to be manufactured so as to leak, according to the present invention, the ratio of the need for reassembly is reduced. The cost for manufacturing can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a portion related to a lock ring of a refrigerator according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a manufacturing procedure of the refrigerator according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Refrigerator 11 Crankcase 12 Hermetic seal 13 Lock ring 15 Motor 16 O-ring 17 Metal seal 22 Tapered surface (seal surface) 32a Groove 31 First seal surface 32 Second seal surface

Continued on the front page (72) Inventor Kazuhiro Nomi 2-1-1 Tanidocho, Tanashi-shi, Tokyo Sumitomo Heavy Industries, Ltd. Tanashi Works (72) Inventor Makoto Mizutani 2-1-1 Tanidocho, Tanashi-shi, Tokyo Sumitomo Heavy Machinery Industries Co., Ltd. Tanashi Factory

Claims (2)

[Claims] And a lock member that is joined to the case member by the lock ring in a state in which a metal seal is sandwiched between the case member having an opening, a lock ring, and the case member. A hermetic seal member for sealing the portion, wherein the metal seal has a Sn content of 25 to 35% by weight.
A refrigerator comprising a Sn-Pb alloy in the range of 2. The refrigerator according to claim 1, wherein the metal seal is a member formed in a ring shape.