JP5622473B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor used for an air conditioner or the like.

  A scroll compressor used for an air conditioner or the like includes a fixed scroll and a turning scroll. Each of the fixed scroll and the orbiting scroll is formed by integrally forming a spiral wrap wall on one surface side of a disk-shaped end plate. The fixed scroll and the orbiting scroll are made to face each other with the lap wall meshed, and the orbiting scroll is caused to make a revolving orbit with respect to the fixed scroll. And the fluid in compression space is compressed by reducing the volume, moving the compression space formed between both lap walls from the outer peripheral side to the inner peripheral side.

  In such a scroll compressor, in order to improve the performance, the height of the wrap wall of the fixed scroll and the orbiting scroll is reduced stepwise from the outer peripheral side toward the inner peripheral side, thereby reducing the fluid compressibility. Some have been improved (for example, see Patent Document 1).

JP 2002-364560 A

However, the scroll compressor including the fixed scroll and the orbiting scroll whose height of the wrap wall gradually decreases from the outer peripheral side toward the inner peripheral side has the following problems.
That is, as shown in FIG. 8, in the fixed scroll 1 or the orbiting scroll 2, at the step portion 4 where the height of the wrap wall 3 gradually decreases, the wall top surface 3 a of the wrap wall 3 and the wall top surface 3 a Stress tends to concentrate on the intersecting portion 4x with the rising wall portion 3b that rises perpendicularly.
When the refrigerant is sucked into the compressor in a liquid state for some reason and the compression operation is performed as it is, the density of the refrigerant in the liquid state is much higher than that in the gas state. There is a problem that cracks occur in the portion 4x. The same problem occurs when foreign matter is caught in the compressor.

  The present invention has been made based on such a technical problem, and an object thereof is to provide a scroll compressor capable of obtaining high durability and reliability.

For this purpose, a scroll compressor according to the present invention includes a main shaft that is rotatably supported in a housing that forms an outer shell, and a orbiting scroll that is rotatably connected to a position offset with respect to the center of the main shaft. A fixed scroll that is fixed to the housing side and that opposes the orbiting scroll and forms a compression space for compressing fluid between the orbiting scroll, the orbiting scroll and the fixed scroll each having a disk shape A spiral wrap wall is integrally formed on the end plate, and a compression space is formed by meshing the wrap wall of the orbiting scroll and the wrap wall of the fixed scroll, and the wrap wall has a rising height from the end plate, The lap wall gradually decreases from the outer peripheral side to the inner peripheral side, and the rising height of the end plate of the wrap wall is the first. The high wall portion having a height, and a bottom wall having a smaller second height than the high walls. At least one of the orbiting scroll and the fixed scroll includes a top surface of the low wall portion and a rising wall portion rising from the low wall portion toward the high wall portion at the step portion between the high wall portion and the low wall portion. The boundary portion is subjected to R processing or chamfering processing with a predetermined radius of curvature or chamfering dimension, and the curvature radius or chamfering dimension of the boundary portion is formed to gradually increase from the outer peripheral side to the inner peripheral side of the wrap wall. It is characterized by.
The orbiting scroll and the fixed scroll perform the compression operation by gradually reducing the volume in the compression space by the relative orbiting operation of both. In the latter half of the compression process, in a state where the pressure in the compression space is high, the compression space is sealed on the inner peripheral side of the wrap wall, so that a high pressure acts on the inner peripheral side of the wrap wall. Therefore, by increasing the radius of curvature of the boundary portion on the outer peripheral side of the wrap wall as much as possible, it is possible to prevent cracks and the like from occurring at the boundary portion between the rising wall portion and the top surface of the low wall portion. On the other hand, in the initial stage where compression of the compression space is started, the compression space is sealed on the outer peripheral side of the wrap wall. Therefore, the boundary portion between the top surface of the low wall portion and the rising wall portion rising from the low wall portion toward the high wall portion by reducing the radius of curvature and chamfering dimension of the boundary portion on the outer peripheral side of the wrap wall as much as possible. It is possible to ensure high meshing accuracy and improve sealing performance.

Here, the boundary portion can be formed such that its radius of curvature or chamfer dimension continuously increases from the outer peripheral side to the inner peripheral side of the wrap wall. In addition, the boundary portion has a constant radius of curvature or chamfered dimension on the outer peripheral side of the wrap wall, and the remaining area on the inner peripheral side of the wrap wall has a radius of curvature or chamfered toward the inner peripheral side of the wrap wall. You may form so that a dimension may become large continuously.
The boundary portion may have a radius of curvature of 0 on the outermost peripheral side of the wrap wall.

According to the present invention, the curvature radius or chamfering dimension of the boundary portion between the top surface of the low wall portion of the wrap wall and the rising wall portion rising from the low wall portion toward the high wall portion is determined from the outer peripheral side of the wrap wall. Since it is formed so as to gradually increase toward the inner peripheral side, at the initial stage where compression of the compression space starts, the top surface of the low wall portion and the rising wall portion that rises from the low wall portion toward the high wall portion It is possible to ensure a high meshing accuracy at the boundary portion and improve the sealing performance. On the other hand, in a state where the pressure in the compression space is high in the latter half of the compression process, it is possible to prevent the occurrence of cracks or the like at the boundary portion between the rising wall portion and the top surface of the low wall portion.
Thereby, high durability and reliability of the scroll compressor can be obtained.

It is a figure which shows the whole structure of the scroll compressor in this Embodiment. It is a figure which shows the meshing state of a fixed scroll and a turning scroll, Comprising: It is sectional drawing in the surface along a main axis | shaft. (A) is a fixed scroll, (b) is a perspective view of a turning scroll. It is a perspective view which shows the structure of the level | step-difference part of the high wall part of a scroll wall, and a low wall part. It is sectional drawing which shows the meshing state of the fixed scroll and turning scroll in the level | step-difference part of a scroll wall. It is a figure which shows the transition of the meshing state of a fixed scroll and a turning scroll. It is a figure which shows the example of distribution of the curvature radius of a boundary part. It is a perspective view which shows the structure of the level | step-difference part of the high wall part of a conventional scroll wall, and a low wall part.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
FIG. 1 is a diagram for explaining a configuration of a scroll compressor according to the present embodiment. In this embodiment, the case where the compressor 10 is used for the refrigerating cycle system for air conditioning is mentioned as an example.
As shown in FIG. 1, the compressor 10 is a vertical scroll type, and includes a main shaft 12, a turning scroll 20 that rotates together with the main shaft 12, and a fixed scroll 30 that is fixed to the housing 11. .
In such a compressor 10, the refrigerant (fluid) is introduced into the housing 11 from the refrigerant introduction port P <b> 1 formed on one end side of the housing 11, and the compression formed between the orbiting scroll 20 and the fixed scroll 30. The refrigerant is compressed in the space. The compressed refrigerant is discharged from a refrigerant discharge port P <b> 2 formed on the other end side of the housing 11.

As shown in FIGS. 1 and 2, the orbiting scroll 20 has a disc-shaped end plate 21 integrally formed with a spiral wrap wall 22 having a predetermined height.
On the other hand, in the fixed scroll 30, a spiral wrap wall 32 is formed on the end plate 31 that faces the orbiting scroll 20 and meshes with the wrap wall 22 of the orbiting scroll 20.

  As shown in FIG. 2, the wrap wall 22 of the orbiting scroll 20 and the lap wall 32 of the fixed scroll 30 have a sealing property at the end plate 31 facing the end plate 31 of the fixed scroll 30 and the end plate 21 of the orbiting scroll 20. In order to enhance, chip seals 28 and 38 made of a resin material or the like are provided.

  In this way, the orbiting scroll 20 and the fixed scroll 30 combine the wrap wall 22 and the wrap wall 32 with each other. Thereby, a compression space 50 is formed between the orbiting scroll 20 and the fixed scroll 30.

  As shown in FIG. 1, the refrigerant introduced into the compression space 50 from the outer peripheral side of the orbiting scroll 20 and the fixed scroll 30 in this way is sequentially moved from the outer peripheral side to the inner peripheral side by the revolution of the orbiting scroll 20 with respect to the fixed scroll 30. Sent and compressed. The refrigerant compressed in the compression space 50 is discharged from a refrigerant discharge port P2 formed on the other end side of the housing 11 via a reed valve 40 attached to an upper cover 39 provided so as to cover the fixed scroll 30. The

  Both ends of the main shaft 12 are rotatably supported by the housing 11 via bearings 13 and 14. The main shaft 12 is rotationally driven by a motor 17 including a stator 15 fixed to the inner surface of the housing 11 and a rotor 16 fixed to the outer peripheral surface of the main shaft 12 and facing the stator 15. The main shaft 12 is driven to rotate by one end of the main shaft 12 projecting outside through the housing 11 and connected to one end of the main shaft 12 by a driving source (not shown) such as an engine or a motor provided outside. You can also

On the other end portion of the main shaft 12, a boss 18 is formed so as to protrude from the central axis of the main shaft 12 by a predetermined amount. A recess 23 that accommodates the boss 18 is formed on the main shaft 12 side of the orbiting scroll 20. The boss 18 is inserted into the recess 23 via a drive bush (bearing) 24, whereby the orbiting scroll 20 is rotatably held by the boss 18. Thereby, the orbiting scroll 20 is provided eccentrically by a predetermined dimension with respect to the center of the main shaft 12, and when the main shaft 12 rotates around its axis, the orbiting scroll 20 is eccentric with respect to the center of the main shaft 12. Performs swivel motion (revolution) with the radius as the dimension An Oldham ring (not shown) is interposed between the orbiting scroll 20 and the main shaft 12 so that the orbiting scroll 20 does not rotate while revolving.
The main shaft 12 has a lubricating oil passage 12 a for supplying the lubricating oil sucked up from the oil reservoir at the bottom of the housing 11 from the upper end portion of the main shaft 12 to the drive bush 24 between the main shaft 12 and the recess 23. Is formed.

  Now, in order to increase the compression rate by gradually reducing the cross-sectional area of the compression space 50 formed between the orbiting scroll 20 and the fixed scroll 30 from the outer peripheral side toward the inner peripheral side, On both surface sides of the end plate 21, the wrap height of the orbiting scroll 20 and the fixed scroll 30 is gradually reduced from the outer peripheral side toward the inner peripheral side.

  To this end, as shown in FIGS. 2 and 3, the end plate 21 of the orbiting scroll 20 is positioned so that the end plate surface 21B of the inner peripheral portion is closer to the fixed scroll 30 than the end plate surface 21A of the outer peripheral portion. It is formed as follows. On the other hand, the end plate 31 of the fixed scroll 30 is formed so that the end plate surface 31B of the inner peripheral portion is located on the orbiting scroll 20 side with respect to the end plate surface 31A of the outer peripheral portion. In the orbiting scroll 20 and the fixed scroll 30, spirally continuous grooves are formed by the end plates 21 and 31 and the spiral wrap walls 22 and 32, and the bottom surfaces of the grooves are the end plate surfaces 21 </ b> A, 21 </ b> B, It is formed of 31A and 31B. The step portion 70 between the end plate surfaces 21A and 31A on the outer peripheral portion and the end plate surfaces 21B and 31B on the inner peripheral portion is formed in a semicircular shape with the interval between the wrap walls 22 and 32 on both sides of the groove as a diameter. ing.

On the other hand, the height of the wrap wall 22 of the orbiting scroll 20 and the wrap wall 32 of the fixed scroll 30 decreases stepwise (stepwise) from the outer peripheral side to the inner peripheral side of the orbiting scroll 20 and the fixed scroll 30. Yes.
As shown in FIGS. 3 and 4, the orbiting scroll 20 and the fixed scroll 30 are configured such that the height of the wrap walls 22 and 32 is changed from the high wall portions 22H and 32H having the first height to the high wall portion 22H, Low wall portions 22L and 32L having a second height lower than 32H are continuously formed. Thereby, the step part 62 is provided between the high wall parts 22H and 32H and the low wall parts 22L and 32L. In the stepped portion 62, a rising wall portion 63 that rises perpendicular to the top surfaces 22t, 32t of the low wall portions 22L, 32L is formed between the high wall portions 22H, 32H and the low wall portions 22L, 32L. The rising wall portion 63 forms the end portion of the high wall portions 22H and 32H. When viewed from above, the rising wall portion 63 has a shape protruding from the high wall portions 22H and 32H into a semicircular shape whose diameter is the thickness dimension of the high wall portions 22H and 32H.

When the orbiting scroll 20 is orbiting with respect to the fixed scroll 30, the wrap walls 22 and 32 have a boundary portion 64 between the lower end portion 63a of the rising wall portion 63 and the top surfaces 22t and 32t of the low wall portions 22L and 32L. However, it operates while meshing with the stepped portion 70 on the bottom surface of the groove.
Here, as shown in FIG. 4, a boundary portion 64 between the lower end portion 63a of the rising wall portion 63 and the top surfaces 22t and 32t of the low wall portions 22L and 32L has an R shape with a predetermined radius of curvature. . Further, the radius of curvature of the boundary portion 64 is formed so as to gradually increase from the outer peripheral side (the outer peripheral side of the end plates 21 and 31) 22O and 32O of the wrap walls 22 and 32 toward the inner peripheral side 22I and 32I. ing.

  On the other hand, the stepped portion 70 also has an R shape that matches the radius of curvature of the boundary portion 64 and that gradually increases in radius from the outer peripheral side toward the inner peripheral side.

Here, FIG. 6 is a diagram showing the transition of the meshing state of the fixed scroll and the orbiting scroll during the compression process, (a) is the first half of the compression process, and (b) is the second half of the compression process. is there.
As shown in FIG. 6B, in the latter half of the compression process, in a state where the pressure of the compression space 50 is high, the rising wall portion 63 and the boundary portion 64 mesh with the stepped portion 70 on the inner peripheral side thereof, so that the compression space 50 is formed. For sealing, high pressure acts on the inner peripheral side of the boundary portion 64. Therefore, it is preferable to increase the reinforcing effect at the boundary portion 64 by increasing the radius of curvature on the inner peripheral side of the boundary portion 64 of the wrap walls 22 and 32. Thereby, even when the refrigerant is compressed in a liquid state, a crack or the like is generated at the boundary portion 64 between the lower end portion 63a of the rising wall portion 63 and the top surfaces 22t and 32t of the low wall portions 22L and 32L. Can be prevented.

  On the other hand, as shown in FIG. 6A, in the initial stage of the compression process, the rising wall 63 and the boundary portion 64 mesh with the stepped portion 70 on the outer peripheral side to seal the compression space 50, and in the latter half of the compression process. In comparison, since a low pressure acts, it is preferable to ensure a high meshing accuracy between the boundary portion 64 and the stepped portion 70 and to improve the sealing performance of the refrigerant in this portion. For this reason, it is preferable to make the radius of curvature of the boundary portion 64 as small as possible on the outer peripheral sides 220, 32O of the wrap walls 22, 32. For example, on the outermost peripheral side of the wrap walls 22 and 32, the radius of curvature r = 0 mm, and the lower end portion 63a of the rising wall portion 63 and the top surfaces 22t and 32t of the low wall portions 22L and 32L may be orthogonal to each other. good.

In addition, in the boundary part 64 and the level | step-difference part 70, as long as it forms so that a curvature radius may become large gradually toward the inner peripheral side from the outer peripheral side 22O, 32O of the lap walls 22 and 32, what kind of structure may be sufficient. .
For example, as shown in FIG. 7A, the radius of curvature of the boundary portion 64 is formed so as to increase continuously from the outer peripheral side 22O, 32O of the wrap walls 22, 32 toward the inner peripheral side 22I, 32I. May be.
Further, for example, as shown in FIG. 7 (b), the radius of curvature of the boundary portion 64 is the same in the constant range S1 of the outer peripheral side 22O, 32O of the wrap walls 22, 32, and the inner peripheral side 22I, 32I In range S2, you may form so that a curvature radius may become large gradually toward an inner peripheral side.

  Further, the boundary portion 64 and the stepped portion 70 may be chamfered instead of R-processed. In this case, the chamfer dimension is changed from the outer peripheral side 22O, 32O of the wrap walls 22, 32 to the inner peripheral side 22I, 32I. It forms so that it may become large gradually toward.

In the above embodiment, the overall configuration of the compressor and the like are not intended to be limited to the configuration described above, and other configurations can be adopted as appropriate.
Moreover, this invention is not restricted to the structure integrated in a refrigerating-cycle system and compressing a refrigerant | coolant with a compressor. For example, the present invention can be applied to a case where a fluid other than the refrigerant is compressed by a compressor.
In addition to this, as long as it does not depart from the gist of the present invention, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate.

  DESCRIPTION OF SYMBOLS 10 ... Compressor, 11 ... Housing, 12 ... Main shaft, 20 ... Orbiting scroll, 21 ... End plate, 22 ... Wrap wall, 22H ... High wall part, 22L ... Low wall part, 22t ... Top surface, 30 ... Fixed scroll, 31 ... End plate, 31A ... End plate surface, 31B ... End plate surface, 32 ... Wrap wall, 50 ... Compression space, 62 ... Stepped portion, 63 ... Rising wall portion, 64 ... Border portion, 70 ... Stepped portion

Claims (4)

A main shaft rotatably supported in a housing forming an outer shell;
A orbiting scroll rotatably connected to a position offset with respect to the center of the main shaft;
A fixed scroll fixed to the housing side, facing the orbiting scroll and forming a compression space for compressing fluid between the orbiting scroll, and
Each of the orbiting scroll and the fixed scroll has a disc-shaped end plate integrally formed with a spiral wrap wall, and the wrap wall of the orbiting scroll and the wrap wall of the fixed scroll are engaged with each other. While forming a compression space, the rising height from the end plate of the wrap wall gradually decreases from the outer peripheral side to the inner peripheral side of the spiral wrap wall,
The wrap wall includes a high wall portion having a first height of the end plate of the wrap wall and a low wall portion having a second height smaller than the high wall portion. Have
At least one of the orbiting scroll and the fixed scroll includes a top surface of the low wall portion and a rising rising from the low wall portion toward the high wall portion at a step portion between the high wall portion and the low wall portion. The boundary portion with the wall portion is subjected to R processing or chamfering processing with a predetermined curvature radius or chamfer dimension, and the curvature radius or chamfer dimension of the boundary portion is directed from the outer peripheral side to the inner peripheral side of the wrap wall. A scroll compressor characterized by being formed to gradually increase.   2. The scroll compressor according to claim 1, wherein the boundary portion is formed such that a radius of curvature or a chamfer dimension thereof continuously increases from an outer peripheral side to an inner peripheral side of the wrap wall. .   The boundary portion has a constant radius of curvature or chamfered dimension on the outer peripheral side of the wrap wall, and the remaining radius on the inner peripheral side of the wrap wall is a radius of curvature toward the inner peripheral side of the wrap wall. The scroll compressor according to claim 1, wherein the scroll compressor is formed so that a chamfer dimension continuously increases.   The scroll compressor according to any one of claims 1 to 3, wherein the boundary portion has a radius of curvature of 0 on the outermost peripheral side of the wrap wall.

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