JPH11257229A - Hermetic compressor and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily automate a shell assembling process by setting both width of a part element for composing a shell and one opening part of the other element to facilitate automatic insertion of the other opening part, and narrowing a clearance between overlapping parts by contracting one opening part from an outer peripheral side after inserting the other opening part. SOLUTION: A diameter of a container opening part 21a for housing a joint in a shell is slightly enlarged, and a clearance is formed between the container opening part 21a and a cover opening part 22a to facilitate automatic insertion of the cover opening part 22a. At the time of assembly, the container opening part 21a is contracted from its outer peripheral side after the cover opening part 22a is automatically inserted into the container opening part 21a by an automatic device, and a size(d) of a clearance 24' between overlapping parts is preferably set to 0.2 mm and less. A clearance is arranged between the cover opening part 22a and the container opening part 21a, and thereby, automatic insertion is facilitated, and the clearance between overlapping parts is uniformly narrowed. It is thus possible to reduce power supply at the time of welding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a hermetic compressor used for a refrigerator or the like.

[0002]

2. Description of the Related Art A hermetic compressor in which a compression element and an electric element of a pump are housed in a shell so that refrigerant does not escape into the atmosphere is well known. In this hermetic compressor, the compression element and the electric element are housed in a part of a shell that wraps the compression element and the electric element, and necessary wiring and piping are processed. The shell is completed by joining the component elements with each other by overlapping the openings, and sealing the joint by welding.

[0003] In the hermetic compressor, when the refrigerant leaks out of the shell (this is called a leak), the cooling capacity of the refrigeration system is reduced. Therefore, the compression element and the electric element are wrapped in the shell. One of the causes of the leak is a defective weld seal at the overlapping portion of the elements constituting the shell. Conventionally, in order to prevent this sealing failure, the gap between the overlapping portions has been made as narrow as possible. However, if the gap is too narrow, the opening of one element cannot be inserted into the opening of the other element. Therefore, the gap is generally designed to be about 0.5 mm.

[0004] The problem in this case will be described below by taking as an example a case where the one element is a container constituting a shell and the other element is a lid. That is, when a lid and a container are formed from a blank material (a flat material) using a mold, the roundness as designed does not appear in the opening, and the dimensions of the gap are determined over the entire circumference of the overlapping portion. , Design dimensions (0.
5 mm) to about ± 1.0 mm.

For this reason, it is difficult to fit the opening of the lid and the opening of the container in a narrow space. Conventionally, the lid is hit and fitted into the container. There was a problem of difficulty.
On the other hand, there is a possibility that molten metal may fall into the shell or sparks may enter the shell in a wide gap.

On the other hand, in order to securely and securely seal the gap between the overlapping portions, it is good to set the welding thickness to 3 mm or more. However, if the welding thickness is increased more than necessary, the welding when the power supply power is increased is increased. The heat strongly heated the plate material of the shell, causing scale to be formed on the back side of the shell and opening the pores in the shell. If this is feared and the seal welding is made as short as necessary, a seal failure occurs at the welded portion, and a leak failure easily occurs. For this reason, airtight tests have traditionally required careful testing, and nevertheless,
Product yield was poor due to leak failure.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method of manufacturing a hermetic compressor, which makes it easy to automate the shell assembling process, has a good yield, and obtains a compressor having excellent airtightness. As an issue.

[0008]

Means for Solving the Problems In order to solve the above problems, a method of manufacturing a hermetic compressor according to the present invention comprises:
The compression element and the electric element are housed in a part of a shell that wraps the compression element and the electric element, and necessary wiring and piping are performed. The other elements and the part of the shell are connected to each other. In a method for manufacturing a hermetic compressor, in which the shell is completed by overlapping and joining the openings by welding and sealing the joint by welding, the width of the opening of one of the partial element and the other element is increased. That is, the width is set to facilitate the automation of the insertion of the other opening, and after the insertion of the other opening, the one opening is narrowed from the outer peripheral side to narrow the gap between the overlapping portions. Features.

[0009]

FIG. 1 shows a cross section of a hermetic compressor. A combined body 1 composed of a compression element and an electric element is hermetically housed in a shell 2. As shown in FIG. 2, the shell 2 includes a container 21 having an opening 21a for accommodating the combined body 1, and a cap-shaped lid 22 for shielding the opening 21a. The container opening 21a is slightly enlarged as shown in the figure. The container 21 is provided with a base piece 21b for fixing the compressor to the foundation. The combined body 1 is stably supported in the container 21 through a spring 23 so as to be hollow. The required wiring 3 for the combination 1
A pipe 4 is provided, and the wiring 3 and the pipe 4 pass through the shell 2 and go out of the shell. Opening 2 of lid 22
2a is inserted into the inside of the opening 21a of the container 21, and the gap 24 of the overlapped portion is sealed with the weld 5, so that the airtightness of the shell 2 is maintained and the lid 22 is fixed to the container 21. In the method of the present invention, the lid 22 is gripped by an automated device such as a robot arm (not shown) or the like, and the lid opening 22a is opened.
Is automatically inserted into the container opening 21a. For this purpose, the inner diameter of the container opening (flange) 21a is set slightly larger than before, and as shown in FIG. 3, automatic insertion of the lid opening 22a between the container opening 21a and the lid opening 22a is performed. A gap 24 for facilitating the formation is formed. Conventionally, the lid opening 22a was inserted into the container opening 21a by tapping the lid 22, but in the method of the present invention, in order to eliminate the tapping and increase the speed of the production line, the gap was made larger than before. I have. However, the gap 24 may slightly hit the lid opening 22a when the lid opening 22a is inserted into the container opening 21a, and should not be too wide unless automatic insertion is difficult. If the width is too wide, a large wrinkle is generated in the container opening 21a in a squeezing step described later, and the gap 24 may be increased somewhere on the entire circumference of the overlapping portion.
The width dimension of the container opening 21a is not particularly limited, but the size D of the gap 24 generated after the insertion of the lid opening is about 1.0 mm on average over the entire circumference, for example, about 0.5 to 1.5 mm. The dimensions are preferably such that Clearance dimension D
If the width is smaller than the above range, automatic insertion tends to be difficult. If the width is larger, a large gap may partially remain after the drawing process.

In the insertion step, the container opening 21
a may be heated and press-fitted by high frequency heating or the like. The reason is that the heating slightly increases the diameter of the container opening 21a, so that a smoother insertion becomes possible. Next, as shown in FIG. 4, the container opening 21a is squeezed from its outer peripheral side, and a gap between the overlapping portions, that is,
It is preferable that the dimension d of the gap 24 'between the lid opening 22a and the container opening 22a be 0.2 mm or less. The gap remains after drawing (reducing) due to the springback of the plate material. In the method of the present invention, the step of squeezing the container opening is thus added. For this reason, the gap between the overlapping portions is sufficiently smaller than before, and is substantially uniform over the entire circumference of the overlapping portion. For this reason, the power supply power for welding can be reduced, and sealing is ensured even if the welding width is reduced.

Although the drawing process is not particularly limited,
As shown in FIGS. 4 and 5, it is preferable to use the squeezing machine 6 in which a large number of pressing portions 61 are arranged at equal intervals on the outer peripheral side of the container opening 21a. In this case, it is preferable that the number of the pressing portions 61 (the number of divisions) is large because wrinkles hardly occur in the container opening 21a after the drawing process. For example, the number is preferably around 18 (divided by 18). When the pressing unit 61 provided in the drawing machine 6 is lowered as shown by a large arrow in FIG. 4, for example, the tapered surface 62a of the pressing unit 62
By pressing the rear end tapered surface 1 in the diagonal arrow direction, the diaphragm operation is performed. It is preferable that the pressing surface of the pressing portion 61 is not an arc surface along the arc surface of the container opening 21a. Rather, it is better not to be circular but horizontal in the horizontal direction. This is because wrinkles are less likely to remain in the container opening 21a after drawing.

FIG. 6 shows a specific example of the drawing machine 6. The squeezing machine 6 presses the lid 22 of the shell 2 placed on the table 69 from above with the pressing tool 64 to fix the shell 2 on the table 69, and causes the pressing tool 64 to pivot on the outer side thereof. The motorized taper ring 65 is attached to the arm 63 which can swing in the radial direction.
Are operated (downward) to press the pressing portions 63a... Provided at the lower end of the arm 63 inward in the radial direction to perform the drawing. Taper ring 65
The vertical movement of the slide guide 68 is achieved by transmitting the rotational force of the motor 66 to the feed screw 67 and obtaining the vertical movement of the slide guide 68 by the feed screw 67.

[0013] Next, the gap slightly remaining in the overlapping portion is sealed by welding. This welding is not particularly limited, but before the start, on the entire circumference of the overlapping portion of the lid opening,
The welding torch is performed after learning the relative position between the tip of the torch and the gap. This means, for example, as shown in FIG.
While the shell 2 is rotated as shown by the arrow in the figure, while the two-dimensional laser scanning sensor 72 is used to fix the gap 24 ′ in the overlapping portion.
The welding torch 73 is made movable, and the tip of the torch 73 is moved up and down and back and forth based on the learning result.
Do. By doing so, the position and shape of the bead are stable over the entire circumference of the overlapped portion, welding is uniform, and high roundness is not required for the shell itself. It is unnecessary. Since the welding width can be further narrowed in combination with the narrowing of the gap, the power of the welding power source can be minimized.

Note that, by fixing and transferring the shell 2 on a pallet (not shown), the learning step and the welding step can be performed separately. Although not shown, if the plate material forming the shell is formed with irregularities by embossing or rib processing, the generation of noise due to the resonance of the shell is easily prevented, and the thickness of the plate material of the shell is reduced by its reinforcing effect. You can do it.

Although the case where the lid opening is inserted into the container opening has been described above, the same applies to the case where the container opening is inserted into the lid opening. In addition, although the container has a bottom, the container may be a simple tubular body and may have a bottom cover in addition to the top cover. Furthermore, although the above example was for a vertical compressor, the same applies to a horizontal compressor.

[0016]

According to the present invention, it is possible to provide a compressor which is easy to automate the shell completion process, has a good compressor yield, and is excellent in airtightness.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a hermetic compressor.

FIG. 2 is a perspective view showing a container and a lid constituting a shell.

FIG. 3 is a partially enlarged cross-sectional view showing a superposed portion when a lid opening is inserted into a container opening when forming a shell.

FIG. 4 is a partially enlarged cross-sectional view showing a step of squeezing a container opening.

FIG. 5 is a plan view showing a state in which a pressing portion of a squeezing machine is arranged on an outer peripheral side of a container opening.

FIG. 6 is a side view for explaining the relationship between the drawing machine and the shell.

FIG. 7 is a side view for explaining a welding process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combined body consisting of a compression element and an electric element 2 Shell 21 Container 21a Container opening 22 Lid 22a Lid opening 24 Gap 6 Drawer 61 Pressing part 63a Pressing part

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Osamu Yamamoto, inventor, 4-5-2-5 Takaidahondori, Higashiosaka-shi, Osaka Matsushita Refrigerator Co., Ltd. 2-5 Inside Matsushita Refrigeration Machinery Co., Ltd. (72) Inventor Kenji Ueda 4-5-2-5 Inside Matsushita Refrigeration Machinery Co., Ltd., Higashi-Osaka City, Osaka Prefecture 4-5-2-5 Matsushita Refrigeration Machine Co., Ltd.

Claims (6)

[Claims] 1. A compression element and an electric element are housed in a part of a shell that wraps the compression element and the electric element, and necessary wiring and piping are performed. In the method for manufacturing a hermetic compressor, one of the above-mentioned partial element and the other element is completed by superposing the openings of each other and joining them together and sealing the joint by welding to complete the shell. The width of the opening is set to a size that facilitates the automation of the insertion of the other opening, and after the insertion of the other opening, the one opening is squeezed from the outer peripheral side, so that the gap between the overlapping portions is reduced. A method for manufacturing a hermetic compressor, characterized by narrowing the diameter. 2. The method for manufacturing a hermetic compressor according to claim 1, wherein a gap generated in the overlapped portion even after the drawing step is set to 0.2 mm or less at any point on the entire circumference of the opening. 3. The method for manufacturing a hermetic compressor according to claim 1, wherein said one opening is widened so that an average gap of 1.0 mm is formed in said overlapping portion. 4. The squeezing machine according to claim 1, wherein the squeezing of the one opening is performed by a squeezing machine having a large number of pressing portions arranged at equal intervals on the outer peripheral side of the one opening. Manufacturing method of hermetic compressor. 5. The welding is performed after the welding torch has been made to learn the relative position between the tip of the torch and the gap on the entire circumference of the overlapping portion before the welding is started. A method for producing a hermetic compressor according to any one of claims 1 to 4. 6. A hermetic compressor obtained by the method according to claim 1.