JPH10141255A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor having high fatigue strength and able to sufficiently withstand strict using conditions, in a scroll compressing mechanism of a scroll compressor. SOLUTION: Root corner parts 6b, 8b of spiral wall bodies 6, 8 of a fixed scroll member 1 and a movable scroll member 2 are provided with such sectional shapes as to prevent stress concentration, and they have high fatigue strength in relation to repeat bending movement to act in the scroll compression operation. Tip corner parts 6c, 8c of the scroll wall bodies 6, 8 have such sectional shapes as not to interfere with the root corner parts 6a, 8b, a compression chamber 15 having the specified capacity is formed between the scroll wall bodies 6, 8 without being affected by the shapes of the root corner parts 6b, 8b, sufficient sealing performance of the compression chamber 15 can be held, and the smooth scroll compression operation can be secured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type compressor having a spiral compression mechanism for performing a scroll compression operation, and more particularly, to a structure of a fixed scroll member and a movable scroll member which are members of the spiral compression mechanism. About.

[0002]

2. Description of the Related Art A scroll type compressor is a kind of rotary compressor, and has a characteristic that it is small, has no valve mechanism, and has a high compression efficiency. It has already been put to practical use.

As shown in FIG. 7, a spiral compression mechanism which is a basic structure of this type of compressor has a fixed scroll member b having a spiral wall a fixed inside a housing (not shown). A movable scroll member d having a spiral wall c that meshes with the spiral wall a is supported in the housing so as to be capable of turning or revolving. The movable scroll member d is drivingly connected to a drive source (not shown) via a crank pin e. f denotes a sealing tip seal fitted along the end surfaces of the spiral wall members a and c, and g denotes a wear-resistant plate mounted on the bottom surface of the fixed scroll member b.

In the spiral compression mechanism thus configured, the movable scroll member d revolves without rotating with respect to the fixed scroll member b by rotating the crank pin e, and the spiral wall The volume of the compression chamber h formed between the bodies a and c decreases while moving toward the center in the radial direction (see FIG. 7 (b) →→).
→ see). By this series of scroll compression operations, the fluid gas sucked from the suction port i is discharged from the discharge port j after being compressed by the compression chamber h.

[0005]

When the fluid gas is compressed, the bending moments are repeatedly applied to the spiral wall members a and c of the scroll members b and d. Scroll member b,
As shown in FIG. 8, each of d has a square (substantially right-angled) cross-sectional shape in which the root corners of the spiral wall bodies a and c have no roundness.

For this reason, stress concentration due to the notch effect tends to occur at the root corners of the spiral wall bodies a and c, and the fatigue strength of this part tends to be remarkably reduced. In the worst case, both the scroll members b and d may be broken from the root corners of the spiral wall bodies a and c.

In particular, recently, attempts have been made to mount this type of compressor on an air conditioner for a vehicle such as a passenger car, that is, to put the compressor into practical use for a vehicle.
Compared to those for ordinary households, it is necessary to secure long-term stable driving performance under severe conditions such as vibration during driving of cars, to save energy for cars and to install it in narrow installation space. It is essential to reduce the size and weight, and the compressor, which is a main component of the compressor, and the scroll members b, d, which are the components thereof, are no exception. For this purpose, both scroll members b and d must be made of a lightweight material such as an aluminum alloy, and have a robust structure capable of obtaining sufficient strength for a long period of time even under severe operating conditions. There has been a strong demand for the development of a workable structure.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a spiral compression mechanism which has high fatigue strength and can sufficiently withstand severe use conditions. An object of the present invention is to provide a scroll compressor having a scroll structure, which is robust and can be reduced in size and weight.

[0009]

In order to achieve the above object, the scroll type compressor according to the present invention has a cross-sectional shape in which the root corners of the scroll wall of the fixed scroll member and the movable scroll member prevent stress concentration. In addition, the tip corner of the spiral wall body of the other scroll member corresponding to this has a cross-sectional shape that does not interfere with the root corner.

In a preferred embodiment, a root corner of the spiral wall has a concave curved cross-sectional shape composed of a continuous arc, and a corresponding distal corner of the spiral wall has a root corner of the spiral wall. The chamfer is large enough not to interfere with the corners.

In the scroll compressor according to the present invention,
During the scroll compression operation due to the relative revolving motion of the fixed scroll member and the movable scroll member, bending moments are repeatedly applied to the scroll walls of both scroll members, and the root corners of these scroll walls prevent stress concentration. , For example, a concave cross-sectional shape composed of a continuous arc, and sufficient fatigue strength is ensured.

Moreover, the tip corner of the scroll wall of the other scroll member corresponding to the root corner of the scroll wall has a cross-sectional shape which is chamfered and does not interfere with the root corner. A compression chamber of a predetermined capacity is formed between the spiral walls of both scroll members without being affected by the shape of the root corner of the spiral wall, and a sufficient sealing property of the compression chamber can be maintained, so that smoothness can be maintained. Scroll compression operation is ensured.

[0013]

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

FIGS. 1 to 6 show the structure of a spiral compression mechanism which is a main part of a scroll type compressor according to the present invention. This scroll type compressor is specifically used for air conditioners for automobiles such as passenger cars. It is for vehicle mounting. As shown in FIG. 1, the spiral compression mechanism mainly includes a fixed scroll member 1 and a movable scroll member 2 that revolve relatively, and these scroll members 1 and 2 are mounted in a housing (not shown). Be done.

The fixed scroll member 1 is a forged integral molded product made of an aluminum alloy, and a scroll wall 6 is integrally provided on a surface 5a of a flat disk-shaped scroll main body 5 in an upright manner. It is fixed in the housing by an appropriate fixing means such as a fixing screw.

On the other hand, the movable scroll member 2 is, like the fixed scroll member 1, a forged integrally formed product made of an aluminum alloy, and is provided on the surface 7a of the flat disk-shaped scroll main body 7 and on the spiral wall body 6. A meshing spiral wall 8 is integrally provided in an upright manner, and is supported in the housing via a thrust bearing (not shown) so as to be capable of turning or revolving. A crankpin 10 is connected to the back surface of the scroll main body 7 of the movable scroll member 2 via a bearing 9, and the crankpin 10 is drivingly connected to a drive source (not shown).

The spiral wall bodies 6 and 8 have the same shape and size, and are engaged with each other in a state where the phases in the rotational direction are relatively shifted by 180 °.
5 are formed. The compression chamber 15 is connected to a suction port (not shown) provided in the housing on the one hand, and is opened to a discharge port 25 penetrating through the center of the movable scroll member 2 of the fixed scroll member 1 on the other hand. I have.

In this connection, the tip surfaces 6a, 8a of the spiral wall bodies 6, 8 are provided on the tip seals 17, 1 for sealing.
8 are attached, and these can be slidably contacted with the bottom surfaces between the opposed spiral wall bodies 6 and 8, respectively. The tip seals 17 and 18 have a spiral shape having a rectangular cross section made of an aluminum alloy-based wear-resistant material. The tip seals 17 and 18 are fitted into fitting grooves formed in the tip surfaces 6a and 8a of the spiral wall bodies 6 and 8, respectively. , Slightly project from the end surfaces 6a, 8a.

In the fixed scroll member 1, a bottom surface between the spiral wall members 6 and 8 is formed by a surface 19a of a wear-resistant plate 19 interposed between the spiral wall members 6, while a movable scroll is formed. In the member 2, the flat surface 7a of the scroll main body 7 is directly formed as it is.

The wear-resistant plate 19 is preferably made of wear-resistant steel, and in the case shown in the figure, is made of a stainless steel plate.
As shown in FIG. 4, the wear-resistant plate 19 has a wear-resistant plate main body 21 having a spiral shape corresponding to the plane between the spiral wall bodies 6, that is, the planar contour of the surface 5 a of the scroll main body 5. At the same time, on both outer peripheral portions of the wear-resistant plate main body 21, the positioning portions 20 are provided over substantially the entire periphery of the wear-resistant plate main body 21 except for the outermost diameter portion. Specifically, the positioning portion 20 is composed of a plurality of positioning pieces 20a, 20a,... Formed intermittently at equal intervals in the circumferential direction on both outer peripheral portions of the wear-resistant plate main body 21. The positioning pieces 20a, 20a,... Abut against the root corners 6b of the spiral wall body 6, respectively, and the wear-resistant plate 19 is positioned and fixed between the spiral wall bodies 6.

The specific arrangement of the positioning pieces 20a, 20a,... May be formed at regular intervals as shown in the drawing, or may be formed intermittently at irregular intervals.

In the above construction, since the bending moment acts repeatedly on the spiral wall bodies 6 and 8 during the scroll compression operation, the following measures are taken at the root corners 6b and 8b.

That is, the root corners 6b and 8b of the spiral wall bodies 6 and 8 have a cross-sectional shape for preventing stress concentration, and preferably have a concave curved cross-sectional shape formed of a continuous arc. Have.

The tip corner 6c of the spiral wall 6 of the other fixed scroll member 1 corresponding to the root corner 8b of the spiral wall 8 of the movable scroll member 2 is connected to the root corner 8b.
Preferably, a chamfer having a size that does not interfere with the root corner 8b is provided.

Further, the positioning portion 2 of the wear-resistant plate 19 is formed corresponding to the sectional shape of the root corner 6b of the spiral wall body 6.
0 (20a, 20a,...) Has a cross-sectional shape that does not interfere with the corresponding root corner 6b of the spiral wall body 6 so that the wear-resistant plate 19 is positioned on the bottom between the spiral wall bodies 6. And are integrally and tightly fixed.

In the illustrated embodiment, the both root corners 6
b and 8b are concave curved cross sections each formed of a single circular arc, that is, a so-called radius processing is performed. In particular,
Referring to FIG. 2, when the curvature radius of the rounded processing to be applied to the base corner portion 8b of the spiral wall 8 of the movable scroll member 2 and R _1, the distal end surface 6a of the spiral wall 6 of the fixed scroll 1 against this Chamfering of the tip corner 6c of C _A + h>
R ₁ (however, C _A : the amount of protrusion of the tip seal 17 from the front end surface 6 a of the spiral wall body 6, that is, the distance between the front end surface 6 a and the bottom surface 7 a, h: the size of the chamfer) Is done.

Further, assuming that the radius of curvature of the radius processing performed on the root corner 6b of the spiral wall body 6 of the fixed scroll 2 is R ₂ , the positioning portions 20 (20a, 20a) of the wear-resistant plate 19 are provided.
a,..) are subjected to a rounding process as shown in FIG. 3A, for example, the radius of curvature R ₃ of the rounding process is set so as to satisfy R ₃ > R _2. You.

Further, the positioning portion 20 (20a, 2
0a,...) From the front end to the base end, that is, the escape amount l
₁ is set to be smaller than the distance l ₂ from the spiral wall body 8 of the orbiting scroll 2 to the side end of the tip seal 18, and considering the radius of curvature of the radius processing of the root corner 6 b in consideration of R ₂ , l
It is set so as to satisfy _2> l _1> R ₂ conditions.

The positioning portion 20 of the wear-resistant plate 19
(20a, 20a,...)
Also in the case where the processing is performed by a combination of an arc and a straight line as shown in (b) or the processing is performed by a combination of different arcs (not shown), the conditions are set so as to satisfy the condition of l ₂ > l ₁ .

In short, the tip seal 18 is located inside the outer peripheral edge of the wear-resistant plate main body 21 and is always in sliding contact with the wear-resistant plate main body 21.

In the scroll compression operation to be described later, the pressure of the fluid gas in the compression chamber 15 increases as the pressure shifts toward the center of the spiral wall bodies 6, 8, and the center of the spiral wall bodies 6, 8 is rounded. The radius of curvature (roundness) may be set larger than that of other portions.

The concrete manufacturing method of each of the above-mentioned components is as follows. For both scroll members 1 and 2, after a thick disk-shaped material is forged by a forging press machine, the spiral is formed by machining. The bottom surface between the wall bodies 6 and 8 is finished flat, and the above-mentioned rounding is performed.

In the wear-resistant plate 19, a metal plate is punched by a press machine to form a spiral shape corresponding to the planar contour between the spiral wall bodies 6 of the fixed scroll member 1 (see FIG. 6A). After the shearing, the positioning portion 20 (20a, 20a,...) Is formed by forging, and a rounding process is performed on the rear surface side portion (see FIG. 6B).

In this case, since the positioning portion 20 is composed of intermittent positioning pieces 20a, 20a,...
Are narrow and limited only to occur in the region of... And their size is also small. Therefore, the wear-resistant plate body 2
1 is very small and the positioning pieces 20a, 20
a,... can be performed with high accuracy, including rounding.

When the crank pin 10 is driven to rotate by the driving source in the scroll compressor having the spiral compression mechanism configured as described above, the movable scroll member 2 moves relative to the fixed scroll member 1. The scroll member revolves without rotating, and a scroll compression operation is performed by the relative revolving motion of the two scroll members 1 and 2.

In this case, a repeated bending moment due to the above-mentioned scroll compressing operation acts on the spiral wall bodies 6, 8 of the scroll members 1, 2, and the root corners 6b, 8b of the spiral wall bodies 6, 8 are formed. As described above, the radius processing is performed to prevent a large stress concentration from occurring at this portion. In other words, the stress concentration (FIG. 5 (b)) in the case of the round cross-sectional shape due to the rounding of FIG.
The stress concentration in the case of the angular cross-sectional shape shown in FIG.
(d)) much smaller.

Therefore, the root corners 6 of the spiral wall bodies 6, 8
The b and 8b have a sufficient fatigue strength. For example, even when the vehicle is operated under severe conditions such as vibration during driving of an automobile, cracks hardly occur at the root corners 6b and 8b, and the operation is performed for a long time. Stable driving performance is ensured.

Moreover, the tip corners 8c, 6c of the other scroll member corresponding to the root corners 6b, 8b of the scroll members 1, 2 do not interfere with the root corners 6b, 8b. A compression chamber 15 having a predetermined capacity is formed between the spiral wall bodies 6 and 8 of the scroll members 1 and 2 without being affected by the shapes of the root corners 6b and 8b. A good sealing property can be maintained, and a smooth scroll compression operation is ensured.

The above-described embodiment merely shows a preferred embodiment of the present invention, and the present invention is not limited to this, and various design changes can be made within the scope.

For example, in the illustrated embodiment, the wear-resistant plate main body 21 is provided only on the fixed scroll member 1 side, but may be provided on the movable scroll member 2 side. In this case, the chamfering of the tip corner 6c of the spiral wall body 6 of the fixed scroll member 1 is not required as in the case of the movable scroll member 2 shown.

In the illustrated embodiment, the cross-sectional shape of the root corners 6b, 8b of the spiral wall bodies 6, 8 has a simple concave curved cross-section made of a single arc by being rounded. However, other cross-sectional shapes that can prevent stress concentration, such as a concave curved cross-sectional shape made of a continuous arc, may be used. Specifically, the cross-sectional shape is adopted in consideration of ease of processing and the like.
Correspondingly, the positioning portion 20 of the wear-resistant plate body 21
The cross-sectional shape of (20a, 20a, ...) is also appropriately changed.

Similarly, the tip corners 6c, 6c of the spiral wall bodies 6, 8
The sectional shape of 8c is not limited to the chamfering process, and another sectional shape that does not interfere with the root corners 6b, 8b can be adopted.

[0043]

As described above, according to the present invention,
In the spiral compression mechanism of the scroll type compressor, the spiral wall of the fixed and movable scroll members, on which the bending moment is repeatedly applied during the scroll compression operation, has a cross-sectional shape at the root corner to prevent stress concentration. Thus, a scroll type compressor having a high scroll structure, which can withstand severe use conditions sufficiently, can be provided, and can be reduced in size and weight.

The tip corner of the scroll wall of the other scroll member corresponding to the root corner of the spiral wall has a cross-sectional shape that does not interfere with the root corner. Without affecting the shape of the scroll member, a compression chamber of a predetermined capacity is formed between the spiral wall bodies of both scroll members, and a sufficient sealing property of the compression chamber can be maintained, so that a smooth scroll compression operation is ensured. .

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a scroll structure of a spiral compression mechanism of a scroll compressor according to one embodiment of the present invention.

FIG. 2 is an enlarged front sectional view showing a main part of the scroll structure.

FIG. 3 is a front sectional view showing a part of a main part of the scroll structure in a further enlarged manner, and FIG. 3 (a) shows an example in which a rounding process is performed on a back surface side of a positioning portion of a wear-resistant plate; FIG. 3 (b) shows an example of a case where a process comprising a combination of a circular arc and a straight line is applied to the back side of the positioning portion of the wear-resistant plate.

FIG. 4 shows the wear-resistant plate of the scroll structure, and FIG.
4 is a plan view, and FIG. 4B is a cross-sectional view taken along line IV-IV in FIG. 4A.

5 shows the degree of stress concentration when an external force is applied to the spiral wall of the scroll member of the scroll structure, and FIG. 5 (a) is a cross-sectional view when the spiral wall is subjected to rounding; 5
(b) is a diagram showing the stress distribution in that case, and FIG. 5 (c) is a cross-sectional view when the spiral wall body is not subjected to radius processing.
FIG. 5D is a diagram showing the stress distribution in that case.

6 (a) and 6 (b) are cross-sectional views showing a state after punching and shearing of a metal plate, and FIGS. 6 (b) and 6 (b) are cross-sectional views showing a method of manufacturing the wear-resistant plate. It is sectional drawing which shows the state after formation.

FIG. 7 (a) shows a scroll structure of a spiral compression mechanism of a conventional scroll type compressor, and FIG.
(b) is a plane sectional view schematically showing the state of the compression chamber during the scroll compression operation.

FIG. 8 is an enlarged front sectional view showing a sectional shape of a spiral wall body in the scroll structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed scroll member 2 Movable scroll member 5, 7 Scroll main body 6, 8 Spiral wall 6a, 8a Tip surface 6b, 8b Root corner of spiral wall 6c, 8c Tip corner of spiral wall 17, Reference Signs 18 chip seal 19 wear-resistant plate 7a, 19a bottom surface of scroll member 20 wear-resistant plate positioning portion 20a positioning-portion positioning piece 21 wear-resistant plate body

Claims (6)

[Claims] 1. A compressor comprising a fixed scroll member and a movable scroll member having a spiral wall body, and performing a scroll compression operation by a relative revolving motion of the pair of scroll members, wherein the spiral wall of the scroll member is provided. The root corner of the body has a cross-sectional shape that prevents stress concentration, and the corresponding tip corner of the spiral wall body of the other scroll member has a cross-sectional shape that does not interfere with the root corner. Scroll type compressor. 2. A root corner of the spiral wall body has a concave curved cross-sectional shape formed of a continuous arc, and a corresponding distal corner of the spiral wall body interferes with the root corner. The scroll type compressor according to claim 1, wherein a chamfer having a size not to be provided is provided. 3. A tip seal that slides on a bottom surface between the opposed spiral wall bodies is attached to a tip end surface of the spiral wall body, and at least the fixed scroll member has
The scroll compressor according to claim 1, further comprising a wear-resistant plate that forms a bottom surface between the spiral wall bodies. 4. The abrasion-resistant plate is provided on an outer peripheral portion of the abrasion-resistant plate body having a spiral shape corresponding to a bottom surface between the spiral wall bodies, and at a corresponding root corner of the spiral wall body. A positioning portion that abuts is provided, and a back surface side portion of the positioning portion has a cross-sectional shape that does not interfere with a root corner of the corresponding spiral wall body, whereby the wear-resistant plate is disposed between the spiral wall body. The scroll compressor according to claim 3, wherein the scroll compressor is integrally fixed to a bottom portion to form the bottom surface between the spiral wall bodies. 5. The scroll compressor according to claim 4, wherein the positioning portion is provided intermittently in a circumferential direction on an outer peripheral portion of the wear-resistant plate main body. 6. The wear-resistant plate main body according to claim 4, wherein the tip seal is located inside the outer peripheral edge of the wear-resistant plate main body and is always in sliding contact with the wear-resistant plate main body. Or the scroll compressor according to 5.