JPS61104173A - Compressor - Google Patents

Abstract

PURPOSE:To reduce the thermal deformation of the sliding fitted portion of a compression mechanism, by spot-welding the frame and enclosing case of an enclosed compressor to each other at the axially intermediate portion of the recess of the frame to prevent the transmission of welding strain. CONSTITUTION:The frame 18 of a compression mechanism is hollowed in the axial direction thereof near the peripheral portion of the frame so that a recess 27 is provided. The compression mechanism and an electric motor are press- fitted in an enclosing case 12. The frame 18 and the case 12 are spot-welded to each other from outside the case at the intermediate portion P of the depth L of the recess 27. This constitution makes it hard for welding heat to be transferred from the bottom 30 of the recess 27 to the slidingly fitted portion of a cylinder 19 or the like. Thermal deformation is thus reduced.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a compressor, and in particular, in a compression mode in which a frame of a compression mechanism section is spot welded to a case, welding deformation of the compression mechanism section that occurs during welding can be avoided. This relates to a compressor that can be effectively suppressed.

[Technical background of the invention and its problems] In a compressor in which a frame of a compression mechanism is fixed to the inner circumference of a cylindrical case by spot welding from the outside, the compression mechanism may be damaged due to thermal stress during welding. There is a risk of deformation.

For this reason, as shown in FIG. 8, in the past, the frame 1
In addition, a through hole 4 is formed along the axial direction of the case 3 near the welded portion 2 in the radial direction, so that the thermal stress is absorbed by the through hole 4.

However, the provision of the through holes 4 has the disadvantage that the rigidity of the frame 1 is reduced and the noise and vibrations of the compressor are increased. The rigidity of the frame 1 can be adjusted by adjusting the diameter of the through-hole 4, but in order to absorb the thermal deformation mentioned above, it is necessary to increase the diameter to some extent, and as long as the through-hole 4 is provided, it cannot be denied that the frame 1 is insufficient in rigidity. There wasn't.

Furthermore, as a method for absorbing thermal deformation without significantly reducing the rigidity, there is also known a structure in which the through hole 4 is formed as a bottomed recess 5, as shown in FIG. If thermal deformation is absorbed by the bottomed recess 5 in this way, the decrease in rigidity will be less compared to the through hole 4, and the generation of noise and vibration can be reduced.

However, in the past, the frame 1 and the case 3 were spot welded near the approximate center of the thickness H of the frame 1, so the bottom 6ff of the recess 5! ! Welding heat was transferred to I, causing thermal deformation to the sliding fitting portion of the compression mechanism section 7, and adversely affecting compression performance and reliability.

[Object of the Invention] The present invention has been made in consideration of the above circumstances, and its purpose is to prevent the transmission of welding strain and to minimize the deformation of the sliding fitting part of the compression mechanism part. An object of the present invention is to provide a compressor that can improve performance and reliability.

[Summary of the Invention] In order to achieve the above object, the present invention provides a compressor in which the outer periphery of a frame of a compression mechanism section is fixed to the inner periphery of a cylindrical case from the outside by spot welding. A recess is formed in the frame by recessing in the axial direction of the case near the outer periphery, and the frame and the case are fixed by spot welding at a position from the axial middle part of the recess to the open end side. By arranging the welding position from the middle of the recess to the open end side, welding heat is mainly absorbed by the case, and welding strain is absorbed by the recess, which is applied to the sliding fitting part of the compression mechanism. Prevent deformation as much as possible.

[Embodiments of the Invention] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

No. 11i<'; EX invention 1 section 6 compressor 8 horizontal type 0-ta
Pressure 1. .

It is a side cross section showing an example of application to a compressor, and Fig. 2 shows its I
It is a sectional view taken along the I-IF line.

As shown in FIGS. 1 and 2, the compressor 11 includes a cylindrical case 12, an electric motor section 13, and a compression mechanism section 14. The electric motor section 13 consists of a stator 15 with a stator core 14 fixed inside the case 72, and a rotor 16 rotatably provided within the stator 15. The rotor 16 and the compression mechanism section 14 are rotatable. They are connected by a shaft 17.

In the compression mechanism section 14, the outer periphery of a frame 18 is fixed to the inner periphery of the case 12 by spot welding from the outside of the case 12. A rotor 21 is provided which is rotationally driven by an eccentric shaft portion 20 . 22 is a blade that divides the inside of the cylinder 19 into a high-pressure side and a low-pressure side, 23 is a blade spring that biases the blade 22 inward in the radial direction, and 24 and 25 are main bearings that pivotally support the rotating shaft 17. and the secondary bearing.

By the way, the feature of the present invention lies in the spot welded portion 26 of the frame 18 of the compression mechanism section 14. As shown in the figure, a recess 27 is formed near the outer periphery of the frame 18 by recessing in the axial direction of the case 12, and at an intermediate position P of the axial depth L of the recess 27, or in the middle thereof. The frame 18 and the case 12 are spot welded at a position closer to the open end 28 of the recess 27 than the position P, and the spot welds 26 are provided at three points in the circumferential direction.

3 and 4 are enlarged side cross-sectional views showing the positional relationship of the spot welds 26, where H is the thickness of the frame 18, L is the depth of the recess, and A is the depth of the recess 27. The dimensions of the welded portion 26 from the open end 28 side are shown.

In the example shown in FIG. 3, the depth L of the recess 27 is
In the example shown in FIG. 4, the depth of the recess 27 is larger than 1/2 of the thickness H of the frame 18.
/2, but the positional dimension A of the spot welded portion 26 from the open end 28 side is smaller than 1/2 of the depth L of the recessed portion 27 and A≦1/2. There is. Further, numeral 29 shown in FIG. 4 is a closing plate that closes the recess 27 to configure it as a sealed chamber and utilize it as a discharge gas passage or a muffler space.

Next, the operation of the present invention will be described.

When the case 12 and the frame 18 of the compression mechanism section 14 are spot-welded, the welding heat causes distortion, which deforms them into sliding joints of internal machines such as the cylinder 19, rotor 21, and blades 22 in the frame 18. However, the welding strain is absorbed by the recess 27 provided near the outer periphery of the frame 18. If the position of the spot weld 26 is close to the bottom 30 of the recess 27, welding heat will be transmitted to the bottom 30 of the recess 27, weakening the welding strain absorption ability of the recess 27. However, in the present invention, the weld Most of the welding heat is absorbed by the case 12 because welding is performed with the position 26 located at the middle of the depth L of the recess 27 or closer to the open end 28 than the depth L of the recess 27 . Therefore, it is possible to prevent welding distortion due to thermal stress from being transmitted to the fitting and sliding portion of the internal mechanical part of the compression mechanism section 14, and the compressive force of the case 12 caused by spot welding can be absorbed by the recess 27.

Therefore, the quality and performance of the compressor can be improved, and the incidence of defects can be reduced.

FIG. 5 is a graph of the measurement results of the amount of distortion in the inner diameter of the cylinder 19 due to a change in the positional dimension A of the weld 26 when the thickness H of the frame 1B is 15 mm and the depth L of the recess 27 is 9III m. .

As is clear from this graph, the positional dimension A of the welded portion 26 is set to 1/2 or less of the depth L −9 mm of the recessed portion 27, that is, A
By setting ≦1/2 (-4.5 mm), it becomes possible to reduce the distortion of the inner diameter of one cylinder as much as possible.

Moreover, FIG. 6 shows a modification of the frame 18a,
FIG. 7 shows a perspective view of the frame 18a.

As shown in FIGS. 6 and 7, the outer peripheral side of the frame 18a has a stepped shape consisting of a large diameter part 31 and a small diameter part 32, and the outer peripheral side of the recess 27 formed in the frame 18a The bottom part 30 of the recessed part 27 has a large diameter "n".
If the outer circumferential side of the portion is made small in diameter with a width W equal to or greater than the wall thickness t of the bottom portion 30 and the outer circumferential side of the bottom portion 30 is separated from the case 12, the welding heat absorbed by the case 12 will be transferred to the frame 18a. The amount of strain caused in the fitting sliding portion of the compression mechanism portion 14 can be further reduced.

In addition, FIG. 6 is a sectional view taken along the line ■-■ in FIG.
In the figure, 33 is a blade storage groove. Further, in the above-described embodiment, a horizontal rotary compressor is illustrated, but the present invention is not limited to this, and the frame 18,
188 may also be formed integrally with the main bearing 24 and the like.

[Effects of the Invention] In summary, the present invention exhibits the following excellent effects.

(1) Most of the welding heat can be absorbed by the case because the spot weld between the case and the frame is placed in the middle of the depth of the recess, or closer to the open end of the recess. Therefore, it is possible to prevent welding distortion due to thermal stress from occurring in the fitting sliding portion of the compression mechanism as much as possible.

(2) Therefore, a high-quality and high-performance compressor can be provided, and the incidence of defects can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing a preferred embodiment of the compressor according to the present invention, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Figs. Fig. 5 is a graph showing an example of changes in the amount of strain in the cylinder inner diameter due to the positional relationship between the spot weld and the recess, and Fig. 6 shows a modified example of the frame. Side sectional view shown, No. 7
The figures are perspective views of the frame shown in Figure 6, Figures 8 and 9.
The figure is a partial side sectional view showing a conventional spot weld. In the figure, 11 is a compressor, 12 is a case, 14 is a compression mechanism, 18 is a frame, and 27 is a recess. Representative Patent Attorney Kensuke Chika (1 other person) Figure 1 n Figure 2 Figure 3 Figure 4 Figure 6 Figure 7 Figure 8 Figure 9

Claims (2)

[Claims] (1) In a compressor in which the outer periphery of the frame of the compression mechanism is fixed to the inner periphery of the case by spot welding from the outside of the cylindrical case, the frame is depressed in the axial direction of the case near the outer periphery. 1. A compressor, characterized in that the frame and case are spot-welded to each other at an axially intermediate position of the recessed portion. (2) Claim 1, wherein the frame has a concave portion formed in the frame with a large diameter outer circumferential side, and a bottom portion of the concave portion of the frame with a small outer circumferential side. Compressor described in section.