WO2014155646A1

WO2014155646A1 - Scroll compressor

Info

Publication number: WO2014155646A1
Application number: PCT/JP2013/059444
Authority: WO
Inventors: 彰士松村; 啓武田; 太田原　優
Original assignee: 日立アプライアンス株式会社
Priority date: 2013-03-29
Filing date: 2013-03-29
Publication date: 2014-10-02
Also published as: EP2980408A1; US20160003247A1; JP6081577B2; JPWO2014155646A1; CN105074218B; CN105074218A; EP2980408A4

Abstract

The purpose of the present invention is to suppress contact between a lap tooth-tip part and a tooth bottom part by enlarging a tooth bottom step, and to reduce the loss caused by a gap formed by enlarging the tooth bottom step. A revolving scroll has: a stationary scroll having a stationary scroll-side flat plate part, and a stationary-side lap that rises while maintaining a swirling shape on a surface of a stationary-side plate part; a revolving-side plate part; and a revolving-side lap that rises while maintaining a swirling shape on a surface of the revolving-side plate part, a compression chamber being formed by the revolving-side lap and the stationary-side lap revolving relative to the stationary scroll while meshing with each other, wherein the tooth bottom step nearer the inner periphery than the outer periphery is formed so as to be larger in either the stationary-side plate part or the revolving-side plate part, and the tooth bottom step is formed so as to be smaller in the revolving-side plate part than the stationary-side plate part on either the outer periphery or the inner periphery.

Description

Scroll compressor

The present invention relates to a scroll compressor.

As a background art in this technical field, there is Japanese Patent No. 2009-281509 (Patent Document 1). In this publication, “a fixed scroll in which a spiral wrap is erected on the inner peripheral portion of the flat plate portion and a cylindrical end plate is provided on the outer peripheral portion so as to surround the wrap; On the opposite surface of the orbiting scroll end plate to the fixed scroll end plate, which is engaged with the end plate facing to the side, the spiral wrap is engaged with the fixed scroll lap to form a plurality of compression chambers. In anticipation of this, it is described in advance that an inclined surface whose thickness decreases from the outer peripheral side to the inner peripheral side is formed, thereby reducing the friction loss caused by the deformation of the fixed scroll and the orbiting scroll. It can improve the efficiency of the compressor "(see summary).

JP 2009-281209 A

In Patent Document 1, a lap tooth is formed on a facing surface of each of the end plates of the orbiting scroll and the fixed scroll by allowing for the deformation of the scroll and forming in advance a tooth bottom having a step difference from the outer peripheral side to the inner peripheral side. It is described that the friction loss due to the contact between the tip portion and the tooth bottom portion facing the tip portion is reduced. In this way, by forming the bottom step, that is, by providing the bottom step, the contact between the lap tooth tip and the bottom portion can be suppressed, but if this bottom step is made too large, a gap is formed on the contrary, Gas leaks into the compression chamber through the gap, and the loss increases.

Therefore, the present invention aims to suppress contact between the lap tooth tip portion and the tooth bottom portion by providing a tooth bottom step and to reduce loss due to a gap formed by increasing the tooth bottom step. And

In order to solve the above problems, for example, the configuration described in the claims is adopted.
The present application includes a plurality of means for solving the above problems.
A fixed scroll having a fixed side plate portion and a fixed side wrap that is erected while maintaining a spiral shape on one surface of the fixed side plate portion;
A revolving side plate portion, and a revolving side wrap that is erected while maintaining a spiral shape on one surface of the revolving side plate portion, and the revolving side wrap and the fixed side wrap are engaged with each other with respect to the fixed scroll. Orbiting scroll that forms a compression chamber by revolving,
An electric motor that drives the orbiting scroll via a crankshaft,
Steps are formed in the tooth bottom portions of the fixed side wrap and the turning side wrap so as to become deeper from the outer peripheral side toward the inner peripheral side,
It is characterized in that the step on the inner peripheral side in the tooth bottom part of the fixed wrap is formed deeper than the step on the inner peripheral side in the tooth bottom part of the turning side wrap ".

According to the present invention, it is possible to reduce the loss due to the gap formed by increasing the tooth bottom step while suppressing the contact between the lap tooth tip portion and the tooth bottom portion by providing the tooth bottom step. It becomes. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

1 is a longitudinal sectional view of a scroll compressor illustrating Example 1. FIG. The block diagram of a fixed scroll and a turning scroll. The figure which showed typically the pressure deformation of the compressor rear part of the scroll compressor of Example 1. FIG. FIG. 3 is a top view of the tooth bottom portion of the orbiting scroll according to the first embodiment. FIG. 3 is a top view of the bottom portion of the fixed scroll according to the first embodiment. The figure explaining the lap structure of a turning scroll and a fixed scroll. FIG. 6 is a diagram illustrating the first embodiment and corresponding to FIG. 5. FIG. 6 is a diagram illustrating the second embodiment and corresponding to FIG. 5. FIG. 7 is a diagram illustrating Example 3 and corresponding to FIG. 6.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the present embodiment, an example of a scroll compressor that optimizes the lap gap and realizes suppression of the lap load and reduction of leakage loss in the compression chamber will be described.
FIG. 1 is an example of a configuration diagram of a scroll compressor according to the present embodiment.
The scroll compressor 1 includes a compression mechanism unit 2, an electric motor 3 that drives the compression mechanism unit 2, and a sealed container 4 that houses the compression mechanism unit 2, the electric motor 3, and the like. This embodiment is a vertical scroll compressor in which the compression mechanism unit 2 is disposed in the upper part of the sealed container 2, the electric motor 3 is disposed in the middle part, and the oil reservoir 15 is disposed in the lower part of the sealed container 4. The sealed container 4 is configured by welding a lid cap 4b and a bottom cap 4c vertically to a cylindrical chamber 4a. A suction pipe 4d is disposed on the lid cap 4b, and a discharge pipe 4e is disposed on the side surface of the cylindrical chamber 4a. A discharge pressure space 4 f serving as a discharge pressure is accommodated in the sealed container 4. In addition, the compression mechanism 2 and the electric motor 3 are accommodated in the discharge pressure space 4f. The compression mechanism unit 2 includes a fixed scroll 5, a turning scroll 6, a frame 7, and the like as basic elements. The fixed scroll 5 and the frame 7 are fastened with bolts, and the orbiting scroll 6 is supported by the frame 7.

FIG. 2 shows a cross-sectional view of the basic configuration of the fixed scroll 5 and the orbiting scroll 6 of the scroll compressor 1 of this embodiment. In FIG. 2, the relative dimensional ratios of the fixed scroll 5 and the orbiting scroll 6 do not always match. The fixed scroll 5 includes a disk-shaped top plate portion (fixed side plate portion 5b), a spiral fixed side wrap 5a erected on the inner peripheral portion of the lower portion of the fixed side plate portion 5b, and a wrapping on the outer peripheral portion of the fixed side plate portion 5b. A cylindrical fixed side end plate portion 5g provided so as to surround 5a, a suction port 5c and a discharge port 5d provided on the upper side of the fixed side plate portion 5b, and the like, are fixed to the frame 7 with bolts. Yes.

The orbiting scroll 6 includes a disk-like orbiting side plate portion 6b on the side where the fixed side wrap 5a of the fixed scroll 5 is erected, and a spiral orbiting orbiting side wrap 6a that is erected on the inner peripheral side of the orbiting side plate portion 6b. It is comprised. The orbiting scroll 6 is disposed so as to be freely rotatable so that the fixed scroll 5 and the lap of each other mesh with each other and a compression chamber 16 is formed. An eccentric pin portion 9b of the crankshaft 9 is connected to the back side of the orbiting scroll 6 (lower side in FIGS. 1 and 2). As the orbiting scroll 6 orbits with respect to the fixed scroll 5, a compression operation is performed in which the volume thereof is reduced.

Each scroll wrap (fixed side wrap 5a, turning side wrap 6a) is formed with a circular involute curve or the like as a basic curve, and is formed outside the wrap on the winding end side of the turning scroll 6 by engaging both scrolls with each other. The outer-line-side compression chamber and the inner-line-side compression chamber formed on the inner side thereof are different in size and have an asymmetric scroll shape formed with a phase shifted by about 180 ° with respect to the rotation of the shaft. The outer peripheral side of the frame 7 is fixed to the inner wall surface of the sealed container 4 by welding or the like, and includes a main bearing 8 that rotatably supports the crankshaft 9.

An Oldham ring 10 is disposed between the rear side of the orbiting scroll 6 and the frame 7. The Oldham ring 10 is mounted in a groove formed on the back side of the orbiting scroll 6 and a groove formed on the frame 7 and receives the eccentric rotation of the eccentric pin portion 9b of the crankshaft 9 without the orbiting scroll 6 rotating. Arranged to revolve.

The electric motor 3 includes a stator 3a and a rotor 3b. The stator 3a is fixed to the sealed container 4 by press-fitting, shrink fitting or the like. The rotor 3b is rotatably arranged inside the stator 3a. The rotor 3b is fixed to the crankshaft 9, and the orbiting scroll 6 is caused to orbit through the crankshaft 9 as the rotor 3b rotates.

The crankshaft 9 is composed of a main shaft 9a and an eccentric pin portion 9b, and is supported by a main bearing 8 and a sub bearing 11 provided on the frame 7. The eccentric pin portion 9b is eccentrically formed integrally with the crankshaft 9a, and is inserted into the orbiting bearing 6d formed on the back surface of the orbiting scroll 6. The crankshaft 9 is driven by the electric motor 3, and the eccentric pin portion 9b rotates eccentrically with respect to the main shaft 9a, thereby driving the orbiting scroll 6. Further, the crankshaft 9 is provided with an oil supply passage 9c for introducing lubricating oil to the main bearing 8, the sub bearing 11, and the slewing bearing 6d, and pumps up the lubricating oil to the lower end on the oil reservoir 15 side and guides it to the oil supply passage 9c. A pump unit 14 is attached. The auxiliary bearing 11 is fixed to the sealed container 4 via the housing 12 and the lower frame 13. The auxiliary bearing 11 rotatably holds one end of the crankshaft main shaft portion 9a on the oil reservoir side using a slide bearing, a rolling bearing, a spherical bearing member, or the like.

When the orbiting scroll 6 is orbitally moved via the crankshaft 9 driven by the electric motor 3, the wraps of the orbiting scroll 6 and the fixed scroll 5 are engaged with each other, and two compression chambers having different sizes (inner side compression chamber, outer line) Side compression chambers) are alternately formed with a phase difference of 180 °. Then, the working fluid such as the refrigerant gas is guided from the suction pipe 4d to the compression chamber 16 formed by the orbiting scroll 6 and the fixed scroll 5, and the volume of the refrigerant gas is reduced and compressed as it moves toward the center of the scroll. Is called. The compressed refrigerant gas is discharged from the discharge port 5d provided at the upper center of the fixed side plate portion 5b of the fixed scroll 5 to the discharge pressure space 4f in the sealed container 4 and circulates around the compression mechanism portion 2 and the electric motor 3. Then, it flows out from the discharge pipe 4e to the outside. Therefore, the space in the sealed container 4 is a so-called high pressure chamber compressor in which the discharge pressure is maintained.

Next, the lubricating oil supply route will be described. A back pressure chamber 17 is formed between the back side of the orbiting scroll 6 and the frame 7, which is a pressure state that is intermediate between the pressure in the suction pipe 4 d and the pressure in the discharge pressure space 4 f. The back pressure chamber 17 is provided in a path through which the lubricating oil passes from the oil reservoir 15 through the oil supply passage 9 c and lubricates the slewing bearing 6 d and then is supplied to the sliding portion of the compression mechanism portion 2. The flat plate portion 6b of the orbiting scroll 6 is provided with a back pressure hole 6c for intermittently communicating the compression chamber 16 and the back pressure chamber 17 formed on the back of the orbiting scroll 6 so that the pressure in the back pressure chamber 17 is sucked into the suction pressure. The discharge pressure is maintained at an intermediate pressure (this intermediate pressure is called back pressure). The orbiting scroll 6 is pressed against the fixed scroll 5 from the back by the resultant force of the back pressure and the discharge pressure acting on the central space on the inner peripheral side of the seal member 18.

Next, pressure deformation of the compression mechanism unit 2 during operation of the compressor will be described.
FIG. 3 is a diagram schematically showing the pressure deformation of the compression mechanism unit 2 of the scroll compressor. As shown in the drawing, since the upper part of the fixed scroll 5 faces the discharge pressure space 4 f, the discharge pressure acts on the upper surface of the fixed scroll 5. Further, since the back surface of the orbiting scroll 6 faces the back pressure chamber 17, back pressure acts on the back surface of the orbiting scroll 6 and pushes the orbiting scroll 6 upward (fixed scroll 5 side).

In the case of the scroll compressor shown in FIG. 3, the fixed scroll 5 is deformed so as to protrude downward (orbiting scroll side) as a whole because the outer edge portion of the fixed side plate portion 5b is fixed to the sealed container 4. Since the orbiting scroll 6 is pressed against the fixed scroll 5 that is deformed downward and convex, the wrap tooth tip portion (fixed wrap tooth tip portion 5e, orbiting side wrap tooth tip portion 6e) and the lap tooth bottom portion of both scrolls are centered. The fixed side wrap tooth bottom 5f and the turning side lap tooth bottom 6f come into contact with each other. Then, each of the fixed scroll 5 and the orbiting scroll 6 is deformed so that the central portion thereof protrudes downward as a whole so as to follow the deformation of the fixed scroll 5. In particular, under the high pressure ratio condition, since the maximum displacement of the lap center portion also increases, the center portion of the fixed wrap tooth tip portion 5e and the center portion of the turning side wrap tooth bottom portion 6f, and the center of the fixed side wrap tooth bottom portion 5f The contact between the portion and the central portion of the turning-side tooth tip portion 6e becomes excessively strong. Therefore, in order to suppress the friction loss and the lap breakage, the bottoms of the orbiting scroll 6 and the fixed scroll 5 (fixed side wrap tooth bottom portion 5f, or orbiting side wrap tooth bottom portion 6f) are respectively moved from the outside toward the center. There is a deeper tooth bottom step. In addition, in each tooth base (fixed side wrap tooth bottom part 5f, turning side wrap tooth bottom part 6f), the distance from the opposing tooth tip (fixed side wrap tooth tip part 5e, turning side wrap tooth tip part 6e) increases. , I will call it the deep root difference.

The characteristics of the step configuration of the lap tooth bottom portion (fixed side wrap tooth bottom portion 5f, turning side wrap tooth bottom portion 6f) will be described.

FIG. 4 is a top view of the orbiting scroll 6 and the fixed scroll 5 of the scroll compressor 1. FIG. 5 is a diagram schematically showing the relationship between the wrap tooth tip and the tooth bottom from the wrap circumferential side surface direction. Here, in FIG. 4 (1), the level difference of the orbiting side wrap tooth bottom portion 6f of the orbiting scroll 6 is the (b) portion along the inner peripheral side with reference to the outermost tooth bottom (c) portion, and further (a ) Is set so that the depth changes in the order of parts. That is, the step is provided so that the innermost (a) portion is deepest and the outermost (c) portion is shallowest.

Further, as shown in FIG. 4 (2), the step of the fixed side wrap tooth bottom portion 5f of the fixed scroll 5 is similar to the turning side wrap tooth bottom portion 6f of FIG. The depth changes in the order of the part (b) and the part (a) along the side, and the amount of change is set equally in the orbiting scroll 6 and the fixed scroll 5. That is, the step is provided so that the innermost (a) portion is deepest and the outermost (c) portion is shallowest.

As shown in FIG. 5, the steps described above are in the order of (b) part and (a) part along the inner peripheral side with reference to the outermost peripheral tooth bottom (c) part in the turning side wrap tooth bottom part 6 f. The depth is set to change. Specifically, the part (a) is formed deeper than the part (c) so as to have a step of 0.02% to 0.04% of the turning wrap tooth height 6h, and the part (b) is (c). 2 is formed with a depth that is a step of 0.005% to 0.02% of the turning wrap tooth height 6h, and further, part (c) is the turning side with respect to the turning end plate surface 6g shown in FIG. It is formed with a depth that provides a step of 0.00% to 0.03% of the lap tooth height 6h. In addition, the turning side wrap tooth height 6h here shows the length from the turning side end plate surface 6g to the turning side wrap tooth tip portion 6e of the turning side wrap 6a as shown in FIG.

On the other hand, the fixed side wrap tooth bottom part 5f is also set so that the depth changes in the order of the part (b) and further the part (a) along the inner peripheral side with reference to the outermost tooth bottom (c) part. Has been. The depth of the step is the same, and the part (a) is deeply formed to be a step of 0.02% to 0.04% of the fixed side wrap tooth height 5h with respect to the part (c), and the part (b) (C) is formed with a depth of 0.005% to 0.02% of the fixed-side wrap tooth height 5h with respect to the portion (c), and the portion (c) with respect to the fixed-side end plate surface 5g shown in FIG. Thus, it is formed with a depth that is a step of the fixed wrap tooth height 5h. As shown in FIG. 2, the fixed side wrap tooth height 5h indicates the length from the fixed side end plate surface 5g to the fixed side wrap tooth tip portion 5e of the fixed side wrap 5a.

4 and 5, when the scroll compressor 1 is driven and pressure and heat are applied to the compression mechanism 2 by the working fluid, the fixed wrap tooth bottom portion 5f and the turning wrap tooth tip portion 6e, Alternatively, the turning side wrap tooth bottom portion 6f and the fixed side wrap tooth tip portion 5e are prevented from excessively contacting each other, and there is an effect of suppressing an increase in input due to friction and improving the reliability of the lap strength.

However, in the scroll compressor having the structure shown in FIGS. 4 and 5, the amount of step difference between the bottom of the fixed wrap tooth bottom portion 5f and the turning side wrap tooth bottom portion 6f is the same, so that the wrap is deformed to the maximum. Even under such conditions, there is a risk that an extra gap will be created. As a result of the study by the present inventors, this is caused by the fact that the step provided in the tooth bottom becomes a gap under operating conditions where the deformation of the lap is small (low speed / low pressure ratio condition), and the refrigerant leaks between the compression chambers. It turns out that there is a problem of loss.

The characteristics of the scroll compressor which is an embodiment for preventing an increase in the leakage loss of the refrigerant from the gap between the wrap tooth tip and the lap tooth bottom will be described with reference to FIGS.

As shown in FIG. 4, the wrap forming surface of the orbiting side plate portion 6 b of the orbiting scroll 6 and the wrap forming surface of the fixed side plate portion 5 b of the fixed scroll 5 have a stepped side so that the step becomes deeper from the outer peripheral side toward the inner peripheral side. A lap tooth bottom portion 6f and a fixed side wrap tooth bottom portion 5f are formed.

FIG. 6 is a view showing the depths of the turning side wrap tooth bottom portion 6f and the fixed side wrap tooth bottom portion 5f of the present embodiment. Here, in the above-described structure described with reference to FIG. 5, the level difference of the part (a) with respect to (c) in the turning side wrap tooth bottom part 6 f and the level difference of the part (a) with respect to (c) in the fixed side wrap tooth bottom part 5 f It was formed to be 0.02% to 0.04% of each lap tooth height and was the same. Further, the step of the portion (b) with respect to (c) in the turning side wrap tooth bottom portion 6f and the step of the portion (b) with respect to (c) in the fixed side wrap tooth bottom portion 5f are 0.005% of the respective lap tooth heights. It was formed to be 0.02% and was the same.

On the other hand, in the structure of the present embodiment shown in FIG. 6, the step of (a) portion with respect to (c) in the turning side wrap tooth bottom portion 6f is different from that of (a) portion with respect to (c) in the fixed side wrap tooth bottom portion 5f. It is characterized by being made smaller than the step. Specifically, the step of the portion (a) with respect to (c) in the turning side wrap tooth bottom portion 6f is formed to be 0.005% to 0.02% of the turning side wrap tooth height 6h, thereby fixing the fixed side wrap. The tooth bottom portion 5f is formed to be smaller than the step of the portion (a) with respect to (c) (0.02% to 0.04% of the fixed side wrap tooth height 5h).

In FIG. 5, if the clearance between the fixed wrap tooth tip 5e and the turning lap tooth bottom 6f in FIG. 5 is hs, and the clearance between the fixed wrap tooth bottom 5f and the turning wrap tooth tip 6e is hk, hs in FIG. = Hk relationship. Further, when the step of the portion (a) with respect to (c) in the turning side wrap tooth bottom portion 6f is Ds and the step of the portion (a) with respect to (c) in the fixed side wrap tooth bottom portion 5f is Dk, as shown above, 5, the relationship is Ds = Dk.

On the other hand, if the gap between the fixed side wrap tooth tip portion 5e and the turning side wrap tooth bottom portion 6f in FIG. 6 is hs', and the gap between the fixed side wrap tooth bottom portion 5f and the turning side wrap tooth tip portion 6e is hk, In FIG. 6, the relationship is hk> hs. Further, when the step difference of the (a) portion with respect to (c) in the turning side wrap tooth bottom portion 6f is Ds' and the step difference of the (a) portion with respect to (c) in the fixed side wrap tooth bottom portion 5f is Dk, Dk as described above. > Ds ′.

This is because, as a result of individually setting the tooth bottom step amount of the orbiting scroll 6 and the fixed scroll 5 in consideration of the pressure and thermal deformation of the orbiting scroll and the fixed scroll, the step amount Ds on the inner peripheral side of the orbiting side wrap tooth bottom portion 6f. ′ (Depth) is made smaller than the step amount Dk (depth) on the inner peripheral side of the fixed side lap tooth bottom part 5f, thereby filling an extra gap and improving the sealing performance. From the gap between the lap tooth tip and the tooth bottom The loss due to the leakage of the refrigerant is suppressed.

In particular, in a scroll compressor using a refrigerant having a low density as a working fluid, for example, an R32 refrigerant, the refrigerant density is smaller than that of the R410A refrigerant, so that the refrigerant is likely to leak between adjacent compression chambers. It is done. Furthermore, in the case of a high-temperature refrigerant such as R32 refrigerant, the temperature during operation becomes high, and expansion of the gap between the lap tooth tip and the lap tooth bottom due to thermal expansion can be considered. According to the present embodiment, it is possible to suppress loss due to refrigerant leakage from the gap between the wrap tooth tip and the tooth bottom due to the provision of the tooth bottom step, so the R32 refrigerant can be used alone or in a refrigeration cycle. A high-performance scroll compressor can be provided even when the ratio of sealing is 70% or more.

Next, a second embodiment of the scroll compressor of the present invention will be described.
FIG. 7 is an example of a configuration diagram schematically showing the relationship between the wrap tooth tip and the tooth bottom from the wrap circumferential side surface direction. The second embodiment is the same as the first embodiment except for the surface shape formed on the lap-facing surfaces of the orbiting scroll 6 and the fixed scroll 5, and the description of the portions having the same functions is omitted.

In the present embodiment, as shown in FIG. 7, in the scroll compressor shown in FIG. 5, the (b) portion and (a) portion in the turning side wrap tooth bottom portion 6f have the same depth as shown in FIG. By making the level difference of the tooth bottom portion 6f into two steps, the gap with the fixed side wrap tooth tip portion 5e at the deepest portion of the turning side wrap tooth bottom portion 6f on the winding start side is reduced. That is, two steps are formed on the fixed wrap tooth bottom 5f, one step is formed on the turning wrap tooth bottom 6f, and fixed by the inner circumferential side step Ds' of the turning lap tooth bottom 6f. It is characterized in that the innermost step Dk in the side wrap tooth bottom portion 5f is formed deeper. In addition, the depth Ds ′ of the inner circumferential side step in the turning side wrap tooth bottom portion 6f and the depth of the second deepest step in the fixed side wrap tooth bottom portion 5f (depth in the (b) portion) are substantially the same. It was confirmed that the loss could be reduced if.

In the present embodiment, the same effect as in the first embodiment can be obtained. Further, since the number of processing steps is reduced by the amount of the step difference with respect to the first embodiment, the manufacturing cost and time can be reduced. Further, the surface from (b) to (c) that faces the fixed wrap tooth tip 5e in FIG. 7 is not perpendicular to the fixed wrap tooth tip 5e as shown in FIG. The slope may be inclined in a slope shape so as to be inclined smoothly. Thereby, the leakage amount of the refrigerant | coolant from the clearance gap which arises in the (c) part which is a level | step difference part can be made small. Further, by making the turning side lap tooth bottom portion 6f into a circumferential step, there is an effect that high-precision machining is easily performed when machining with an end mill. These configurations of the present embodiment can be applied to other embodiments.

Next, a third embodiment of the scroll compressor of the present invention will be described.
FIG. 8 is an example of a configuration diagram schematically showing the relationship between the wrap tooth tip and the tooth bottom from the wrap circumferential side surface direction. The present embodiment is the same as the first embodiment except for the surface shape formed on the lap-facing surfaces of the orbiting scroll 6 and the fixed scroll 5, and the description of the parts having the same functions is omitted.

In this embodiment, as shown in FIG. 8, in the second embodiment shown in FIG. 7, the swivel wrap tooth bottom portion 6 f of the swivel wrap tooth bottom portion 6 f is set shallow, with the bottom step height of the swivel wrap tooth bottom portion 6 f being two steps. With respect to the depth of the (a) part of the (a) part and the (a) part of the fixed-side wrap tooth bottom part 5f, the turning-side wrap tooth bottom part 6f is such that Ds = 1 / 2Dk. That is, in FIG. 8, the depth Ds ′ of the innermost circumferential step in the turning-side lap tooth bottom portion 6f is about half of the depth of the deepest step Dk in the fixed-side lap tooth bottom portion 5f.

It has been confirmed that this makes it possible to reduce the loss without contacting the wrap tooth tip. In this embodiment, the same effects as those of

Embodiments

1 and 2 can be obtained. In addition, the depth of the bottom of the orbiting scroll is set to half the depth of the bottom of the fixed scroll, which reduces the amount of cutting during machining, shortens the machining time, and extends the tool life. There is an effect said.

Next, a fourth embodiment of the scroll compressor of the present invention will be described.
The present embodiment is the same as the first to third embodiments except that the ferrite magnet motor is embedded in the rotor of the electric motor 3 of the scroll compressor, and the description of the portions having the same functions is omitted. To do.

Since ferrite magnet motors are less expensive than neodymium magnet motors, compressors that employ ferrite magnet motors can be expected to significantly reduce costs. However, the ferrite magnet motor has a problem that the efficiency particularly in the low speed region is lower than that of the neodymium magnet motor. Therefore, if the first to fourth embodiments are applied, the level difference (depth) of the bottom 6f of the orbiting scroll 6 is set smaller than the level difference (depth) of the bottom 5f of the fixed scroll 5, thereby improving the sealing performance. Since the loss due to refrigerant leakage from the gap between the lap tooth tip and the tooth bottom can be reduced, a highly efficient and low cost scroll compressor can be provided even in a low speed region.

Next, a sixth embodiment of the scroll compressor of the present invention will be described.
The present embodiment is the same as the first to fourth embodiments except that the refrigerant used for the scroll compressor is a single R32 refrigerant, and the description of the portions having the same functions is omitted.
The R32 refrigerant has a global warming potential (GWP) of 675 and about 1/3 of R410A, and is a refrigerant with less environmental load. However, compared to refrigerants such as R410A, the density is small and the refrigerant leaks easily from the sealed space. When the R32 refrigerant is used, the operating temperature becomes high. There is a problem that the gap between the two becomes large.

Therefore, after applying Examples 1 to 4, the refrigerant sealed in the refrigeration cycle is set to a ratio of about 70% or more of the R32 refrigerant alone or the refrigerant sealed in the refrigeration cycle. As a result, the level difference (depth) of the tooth bottom 6f of the orbiting scroll 6 is set to be smaller than the level difference (depth) of the tooth bottom 5f of the fixed scroll 5, so that an extra gap is filled and the sealing performance is improved. Since loss due to refrigerant leakage from the gap between the tooth tip and the tooth bottom can be reduced, a highly efficient scroll compressor can be provided while using a refrigerant with a small environmental load.

DESCRIPTION OF SYMBOLS 1 Scroll compressor 2 Compression mechanism part 3 Electric motor (3a: Rotor, 3b: Stator)
4 Sealed container (4a: cylindrical chamber, 4b: lid cap, 4c: bottom cap, 4d: suction pipe, 4e: discharge pipe, 4f: discharge space)
5 fixed scroll (5a: fixed side wrap, 5b: fixed side plate portion, 5c: suction port, 5d: discharge port, 5e: fixed side wrap tooth tip portion, 5f: fixed side lap tooth bottom portion, 5g: fixed side end plate surface, 5h: Fixed side wrap tooth length)
6 orbiting scroll (6a: orbiting side lap, 6b: orbiting side plate portion, 6c: back pressure hole, 6d: orbiting bearing, 6e: orbiting side lap tooth tip, 6f: orbiting side lap tooth bottom, 6g: orbiting side end plate surface 6h: Turning wrap tooth height)
7 Frame 8 Main bearing 9 Crankshaft (9a: Main shaft, 9b: Eccentric pin part, 9c: Oil supply passage)
DESCRIPTION OF SYMBOLS 10 Oldham ring 11 Sub bearing 12 Housing 13 Lower frame 14 Pump part 15 Oil reservoir 16 Compression chamber 17 Back pressure chamber

Claims

A fixed scroll having a fixed side plate portion, and a fixed side wrap that is erected while holding a spiral shape on one surface of the fixed side plate portion;
A revolving side plate portion, and a revolving side wrap that is erected while maintaining a spiral shape on one surface of the revolving side plate portion, and the revolving side wrap and the fixed side wrap are engaged with each other with respect to the fixed scroll. Orbiting scroll that forms a compression chamber by revolving,
An electric motor that drives the orbiting scroll via a crankshaft,
Steps are formed in the tooth bottom portions of the fixed side wrap and the turning side wrap so as to become deeper from the outer peripheral side toward the inner peripheral side,
A scroll compressor, wherein a step on an inner peripheral side in a tooth bottom portion of the fixed wrap is deeper than a step on an inner peripheral side in a tooth bottom portion of the turning side wrap.
The scroll compressor according to claim 1, wherein
Two steps are formed at the tooth bottom of the fixed side wrap,
A step of one step is formed at the tooth bottom of the turning side wrap,
A scroll compressor characterized in that the innermost circumferential step at the bottom of the fixed wrap is deeper than the inner circumferential step at the bottom of the turning wrap.
The scroll compressor according to claim 2,
A scroll compressor characterized in that a depth of a step on an inner peripheral side in a tooth bottom portion of the turning side wrap and a depth of a second deepest step in a tooth bottom portion of the fixed side wrap are substantially the same.
The scroll compressor according to claim 1, wherein
The scroll compressor characterized in that the depth of the innermost circumferential step at the tooth bottom portion of the turning side wrap is about half of the depth of the deepest step at the tooth bottom portion of the fixed side wrap.
The scroll compressor according to claim 1, wherein
A scroll compressor characterized in that the depth of the innermost circumferential step at the tooth bottom of the turning side wrap is in the range of 0.005% to 0.02% of the turning side wrap tooth height 6h.
The scroll compressor according to any one of claims 1 to 5,
The scroll compressor according to claim 1, wherein the electric motor is a ferrite magnet electric motor including a stator and a rotor, and a ferrite magnet is embedded in the rotor.
The scroll compressor according to any one of claims 1 to 5,
The scroll compressor characterized by the refrigerant | coolant enclosed with a refrigerating cycle being the ratio of about 70% or more of R32 refrigerant | coolant single-piece | unit or the refrigerant | coolant enclosed with a refrigerating cycle.