WO2019003335A1

WO2019003335A1 - Scroll compressor and refrigeration cycle device

Info

Publication number: WO2019003335A1
Application number: PCT/JP2017/023717
Authority: WO
Inventors: 哲英横山; 岩崎　俊明; 哲仁 ▲高▼井
Original assignee: 三菱電機株式会社
Priority date: 2017-06-28
Filing date: 2017-06-28
Publication date: 2019-01-03
Also published as: JPWO2019003335A1; JP6745994B2

Abstract

This scroll compressor is provided with: a frame which slidably retains an orbiting scroll; a fixed scroll which together with the orbiting scroll forms a compression chamber; and a shell which fixes the fixed scroll separately from the frame; wherein the shell includes a cylindrical main shell containing a thick-walled portion and a thin-walled portion formed with a thin wall and having an inner diameter greater than that of the thick-walled portion, and the fixed scroll includes a placement end portion which is placed on a boundary part of the thick-walled portion and the thin-walled portion, an annular protrusion which has a large diameter at least equal to that of the placement end portion and is in contact with an inner wall portion of the thin-walled portion, and a small-diameter end portion which is on the opposite side to the placement end portion, across the annular protrusion, and has a smaller diameter than the annular protrusion.

Description

Scroll compressor and refrigeration cycle apparatus

The present invention relates to a scroll compressor and a refrigeration cycle apparatus in which a fixed scroll is fixed to a shell separately from a frame.

As the scroll compressor, for example, those disclosed in

Patent Documents

1 and 2 are known. In the scroll compressors of

Patent Documents

1 and 2, the oscillating scroll is supported by a frame fixed to the shell. A fixed scroll is provided opposite to the oscillating scroll. A drive shaft having a rotating shaft and a driving shaft is attached to the oscillating scroll. As the drive shaft rotates, the oscillating scroll revolves with respect to the fixed scroll. Due to this revolution, the refrigerant is compressed in the compression chamber formed by the swing scroll and the fixed scroll.

Japanese Patent Application Laid-Open No. 2-5779 JP, 2009-243363, A

In the scroll compressor, a compression chamber for compressing the refrigerant is formed between the fixed scroll and the oscillating scroll. Therefore, the positional accuracy of the fixed scroll with respect to the oscillating scroll is important.

In the scroll compressor of Patent Document 1, the outer peripheral wall portion of the frame extends in the direction of the fixed scroll, and the fixed scroll is fixed by a bolt or the like at the tip of the outer peripheral wall portion. In this manner, by fixing the fixed scroll to the frame, positional accuracy is secured.

However, in recent years, the introduction of a low GWP refrigerant or the like operating at low density has been considered as a measure against global warming. In order to secure the same capacity as conventional HFC refrigerants with such refrigerants, it is an issue to expand the displacement volume of the compression chamber while keeping the shell the same size.

Here, in the scroll compressor of Patent Document 1, when the upper end portion of the main shell is welded to the upper shell, the inner diameter of the upper end portion of the main shell shrinks by about 1% to 2%. Then, on the outer peripheral surface of the circular base plate of the fixed scroll fixed to the inner wall of the main shell by shrink fitting or the like, a surface pressure distribution that increases from the lower end to the upper end occurs. Bending moment works to make it dent. As a result, the circular base plate and the scroll formed on the lower side are deformed. As a result, the tips of the scroll of the fixed scroll and the scroll of the oscillating scroll contact with each other. And the problem that durability and reliability of a scroll compressor fall will arise.

In the scroll compressor of Patent Document 2, when the upper end of the main shell is welded to the upper shell, the inner diameter of the upper end of the main shell shrinks by about 1% to 2%. Then, a surface pressure distribution that increases from the upper end to the lower end is generated on the outer peripheral surface of the circular base plate of the fixed scroll fixed to the inner wall of the upper shell by shrink fitting or the like. Bending moment works to make it convex. As a result, the circular base plate and the scroll formed on the lower side are deformed. The clearance between the tips of the fixed scroll scroll and the scroll scroll scroll increases. Then, the leakage loss of the scroll compressor increases, which causes a problem of a reduction in the compressor efficiency.

The present invention is intended to solve the above problems, and the fixed scroll can be disposed within the shell with high positional accuracy, and the tips of the scroll of the fixed scroll and the scroll of the oscillating scroll have an appropriate positional relationship. It is an object of the present invention to provide a scroll compressor and a refrigeration cycle apparatus configured to be.

A scroll compressor according to the present invention comprises a frame slidably holding an oscillating scroll, a fixed scroll forming a compression chamber together with the oscillating scroll, and a shell fixing the fixed scroll separately from the frame. And the shell includes a cylindrical main shell including a thick portion and a thin portion formed to be thinner than the thick portion, and the fixed scroll includes the thick portion and the thick portion. The mounting end placed at the boundary with the thin portion, the annular protrusion larger in diameter than the mounting end and contacting the thin portion, and the mounting end being the annular protrusion And a small diameter end smaller in diameter than the annular projection on the opposite side of

A refrigeration cycle apparatus according to the present invention includes the above-described scroll compressor.

According to the scroll compressor and the refrigeration cycle device according to the present invention, the fixed scroll has a mounting end portion mounted at the boundary between the thick portion and the thin portion, and a larger diameter than the mounting end portion. And a small diameter end which is smaller in diameter than the annular projection on the opposite side of the placement end from the annular projection. Here, when the end of the thin portion of the main shell is welded to the end shell, the inner diameter of the end of the thin portion of the main shell shrinks by about 1% to 2%. At that time, since the fixed scroll has the small diameter end, the bending moment received from the end of the thin portion where the small diameter end is contracted can be reduced. As a result, in the fixed scroll fixed to the inner wall of the main shell by shrink fitting or the like, a surface pressure distribution that increases from the mounting end toward the small diameter end does not occur on the outer peripheral surface. There is no bending moment that causes the center to be depressed downward. Therefore, the fixed scroll can be disposed within the shell with high positional accuracy, and the tips of the scroll of the fixed scroll and the scroll of the oscillating scroll have an appropriate positional relationship.

It is explanatory drawing which shows the longitudinal cross-section of the scroll compressor which concerns on Embodiment 1 of this invention. It is a disassembled perspective view which shows the periphery structure of the main frame of the scroll compressor which concerns on Embodiment 1 of this invention. It is an enlarged view which shows the dashed-dotted line area | region A of FIG. 1 whose circumference of the upper shell which concerns on Embodiment 1 of this invention quantifys the shape change of the main shell after welding, and the circular base plate of a fixed scroll. It is explanatory drawing which shows the wall surface part of the main shell which concerns on Embodiment 1 of this invention by a longitudinal cross-section. The circumference of the upper shell in a comparative example is an explanatory view showing the measurement range about the shape change of the main shell after welding, and the circular base plate of a fixed scroll. It is a figure which shows the variation | change_quantity of a shell shape regarding the circumference of the upper shell in a comparative example regarding the shape change of the main shell after welding, and the circular base plate of a fixed scroll. The circumference of the upper shell in a comparative example is a figure showing the surface pressure of a circular base plate peripheral face regarding the shape change of the main shell after welding, and the circular base plate of a fixed scroll. It is explanatory drawing which shows the measurement range regarding the circumference of the upper shell in Embodiment 1 of this invention regarding the shape change of the main shell after welding, and the circular base plate of a fixed scroll. It is a figure which shows the variation | change_quantity of a shell shape regarding the circumference of the upper shell which concerns on Embodiment 1 of this invention regarding the shape change of the main shell after welding and the circular base plate of a fixed scroll. It is an enlarged view which shows the dashed-dotted line area | region A of FIG. 1 with which the circumference of the upper shell which concerns on Embodiment 2 of this invention quantifys the shape change of the main shell after welding, and the circular base plate of a fixed scroll. The figure which shows the state after shrinkage-fitting of a fixed scroll in the dashed-dotted line area | region A of FIG. 1 which quantifies the shape change of the main shell concerning the modification 1 of Embodiment 2 of this invention, and the circular base plate of a fixed scroll. is there. Quantifying the shape change of the main shell and the circular base plate of the fixed scroll according to the first modification of the second embodiment of the present invention FIG. The figure which shows the state after shrinkage-fitting of a fixed scroll in the dashed-dotted line area | region A of FIG. 1 which quantifies the shape change of the main shell which concerns on the modification 2 of Embodiment 2 of this invention, and the circular base plate of a fixed scroll is there. Quantifying the shape change of the main shell and the circular base plate of the fixed scroll according to the modification 2 of the embodiment 2 of the present invention FIG. It is an enlarged view which shows the dashed-dotted line area | region A of FIG. 1 with which the circumference of the upper shell which concerns on Embodiment 3 of this invention quantifys the shape change of the main shell after welding, and the circular base plate of a fixed scroll. It is an enlarged view which shows the dashed-dotted line area | region A of FIG. 1 with which the circumference of the upper shell which concerns on Embodiment 4 of this invention quantifies the shape change of the main shell after welding, and the circular base plate of a fixed scroll. It is an enlarged view which shows the circular base plate of the fixed scroll which concerns on the modification 1 of Embodiment 4 of this invention. It is an enlarged view which shows the circular base plate of the fixed scroll which concerns on the modification 2 of Embodiment 4 of this invention. It is an enlarged view which shows the circular base plate of the fixed scroll which concerns on the modification 3 of Embodiment 4 of this invention. It is an enlarged view which shows the circular-shaped board of the fixed scroll which concerns on Embodiment 5 of this invention. It is an enlarged view which shows the dashed-dotted line area | region A of FIG. 1 with which the circumference of the upper shell which concerns on Embodiment 5 of this invention quantifys the shape change of the main shell after welding, and the circular base plate of a fixed scroll. It is a refrigerant circuit figure showing the frozen cycle device to which the scroll compressor concerning Embodiment 6 of the present invention is applied.

Hereinafter, embodiments of the present invention will be described based on the drawings. In the drawings, the same reference numerals denote the same or corresponding parts, which are common to the whole text of the specification. Furthermore, the form of the component shown in the specification full text is an illustration to the last, and is not limited to these descriptions.

Embodiment 1
<Overall Configuration of Scroll Compressor>
FIG. 1 is an explanatory view showing a longitudinal cross section of a scroll compressor 100 according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view showing the peripheral structure of the main frame 2 of the scroll compressor 100 according to Embodiment 1 of the present invention.

The scroll compressor 100 shown in FIG. 1 is a so-called vertical scroll compressor in which a central axis of a drive shaft 6 having a rotation shaft and a driving shaft is substantially perpendicular to the ground.

The scroll compressor 100 includes a shell 1, a main frame 2, a compression mechanism portion 3, a drive mechanism portion 4, a sub frame 5, a drive shaft 6, a bush 7, and a power feeding portion 8. In the following, with reference to the main frame 2, the upper side where the compression mechanism portion 3 is provided is directed to the one end side U, and the lower side where the drive mechanism portion 4 is provided as the other end side L.

The shell 1 is a sealed container which is a cylindrical casing made of a conductive member such as metal and closed at both ends. The shell includes a main shell 11, an upper shell 12 as an end shell, and a lower shell 13.

The main shell 11 has a cylindrical shape extending in the axial direction. The suction pipe 14 is connected to the main shell 11 by welding. The suction pipe 14 is a pipe for introducing the refrigerant into the shell 1 and communicates with the inside of the main shell 11.

Upper shell 12 is a substantially hemispherical end shell. A part of the side wall portion of the upper shell 12 is joined to the end of the one end side U of the main shell 11 by welding the circumference. Thereby, one end side U of the main shell 11 is fixed to the upper shell 12. The upper shell 12 closes the opening at one end side U of the main shell 11.

The discharge pipe 15 is connected to the upper portion of the upper shell 12 by welding. The discharge pipe 15 is a pipe that discharges the refrigerant to the outside of the shell 1. The discharge pipe 15 communicates with the discharge space 91 in the main shell 11.

The lower shell 13 is a substantially hemispherical end shell. The lower shell 13 is joined to the main shell 11 in the same manner as the upper shell 12.

The shell 1 is supported by a fixed base 17 provided with a plurality of bolt holes. The fixing base 17 is formed with a plurality of bolt holes. By inserting bolts into these bolt holes, the scroll compressor 100 is fixed to another member such as the casing of the outdoor unit of the air conditioner.

Main frame 2 is accommodated in shell 1. The main frame 2 is a hollow metal frame in which a cavity is formed in the center. The main frame 2 includes a main body portion 21, a main bearing portion 22, and an oil return pipe 23.

The main body portion 21 is fixed to the first projecting portion 112 on the one end side U of the main shell 11. An accommodation space 211 is formed at the center of the main body 21 along the longitudinal direction of the shell 1 which is the same as the extension direction of the central axis of the drive shaft 6. One end side U of the accommodation space 211 is open. The accommodation space 211 is formed in a step-like shape in which the internal space narrows from one end U to the other end L.

An annular flat surface 212 surrounding the housing space 211 is formed on one end side U of the main body 21. On the flat surface 212, a ring-shaped thrust plate 24 made of a steel plate material such as valve steel is disposed. The thrust plate 24 functions as a thrust bearing.

A suction port 213 is formed at a position not overlapping the thrust plate 24 on the outer end side of the flat surface 212. The suction port 213 is a space which penetrates the main body 21 in the vertical direction, that is, the main body 21 between the one end U and the other end L. The number of suction ports 213 is not limited to one, and a plurality of suction ports may be formed.

An oldham housing portion 214 is formed on the step portion on the other end L side of the flat surface 212 of the main frame 2. A pair of first oldham grooves 215 is formed in the oldham housing portion 214. The first Oldham groove 215 is formed such that a part on the outer end side cuts the inner end side of the flat surface 212. Therefore, when the main frame 2 is viewed from one end side U, a part of the first Oldham groove 215 overlaps the thrust plate 24. The pair of first Oldham grooves 215 are formed to face each other.

The main bearing portion 22 is continuously formed on the other end side L of the main body portion 21. In the inside of the main bearing portion 22, an axial hole 221 is formed. The axial hole 221 penetrates in the vertical direction of the main bearing portion 22 and communicates with the accommodation space 211 at one end side U.

The oil return pipe 23 is a pipe that returns the lubricating oil accumulated in the housing space 211 to an oil sump inside the lower shell 13. The oil return pipe 23 is inserted and fixed in an oil drain hole formed to penetrate the inside and the outside of the main frame 2.

The lubricating oil is, for example, a refrigerator oil containing an ester synthetic oil. The lubricating oil is stored in the lower part of the shell 1, that is, in the lower shell 13. The lubricating oil to be stored is sucked up by the oil pump 52 described later, passes through the oil passage 63 in the drive shaft 6, and reduces the wear of the mechanically contacting parts such as the compression mechanism 3 and the like. Adjust the temperature and improve the sealability. As the lubricating oil, it is preferable to use an oil having an appropriate viscosity, as well as excellent lubricating properties, electrical insulation, stability, refrigerant solubility, low temperature fluidity, and the like.

The compression mechanism unit 3 is a compression mechanism that compresses a refrigerant. The compression mechanism unit 3 is a scroll compression mechanism provided with a fixed scroll 31 and an oscillating scroll 32.

The fixed scroll 31 is made of metal such as cast iron. The fixed scroll 31 includes a first circular base plate 311 and a first spiral body 312.

The first circular base plate 311 is configured in a disk shape. At the center of the first circular base plate 311, a discharge port 311a penetrating in the vertical direction is formed.

The first spiral body 312 protrudes from the other end side L surface of the first circular base plate 311 to form a spiral wall.

The oscillating scroll 32 is made of metal such as aluminum. The rocking scroll 32 includes a second circular base plate 321, a second spiral body 322, a cylindrical portion 323, and a pair of second Oldham grooves 324.

The second circular base plate 321 is formed in a disk shape. The second circular base plate 321 connects the surface of the one end side U, the surface of the other end side L in front and back relation to the surface of the one end side U, the surface of the one end side U and the surface of the other end side L And an outer peripheral surface.

The second spiral body 322 is formed on the surface of the one end side U. A sliding surface is formed on at least a part of the outer region on the surface of the other end L. The sliding surface is supported or supported on the main frame 2 so as to be slidable on the thrust plate 24.

The second spiral body 322 protrudes from the surface of the one end side U of the second circular base plate 321 to form a spiral wall. A seal member for suppressing the leakage of the refrigerant is provided at the leading end of the first scroll 312 of the fixed scroll 31 and the second scroll 322 of the oscillating scroll 32.

The cylindrical portion 323 is a cylindrical boss that protrudes from substantially the center of the surface on the other end L of the second circular base plate 321 to the other end L. On the inner peripheral surface of the cylindrical portion 323, a central axis of a so-called journal bearing, which supports a slider 71 described later rotatably, is provided parallel to the central axis of the drive shaft 6.

The second Oldham groove 324 is an elongated round groove formed on the surface of the other end L of the second circular base plate 321. The pair of second Oldham grooves 324 are provided to face each other. The line connecting the pair of second Oldham grooves 324 is orthogonal to the line connecting the pair of first Oldham grooves 215.

An Oldham ring 33 is provided in the Oldham accommodation portion 214 of the main frame 2. The Oldham ring 33 includes a ring portion 331, a pair of first key portions 332, and a pair of second key portions 333.

The ring portion 331 is annularly configured. The pair of first key portions 332 is formed to face the surface on the other end L of the ring portion 331. Each of the pair of first key portions is accommodated in each of the pair of first oldham grooves 215 of the main frame 2. The pair of second key portions 333 is formed to face the surface on one end side U of the ring portion 331. Each of the pair of second key portions is accommodated in each of the pair of second Oldham grooves 324 of the oscillating scroll 32.

When the swing scroll 32 revolves due to the rotation of the drive shaft 6, the first key portion 332 slides in the first oldham groove 215, and the second key portion 333 slides in the second oldham groove 324. . Thereby, the Oldham ring 33 prevents rotation of the rocking scroll 32.

A compression chamber 34 is formed by the first scroll 312 of the fixed scroll 31 and the second scroll 322 of the oscillating scroll 32 being engaged with each other. The volume of the compression chamber 34 decreases in the radial direction from the outside to the inside. Therefore, the refrigerant is gradually compressed when taken in from the outer end side of the first spiral and the second spiral 322 and moving to the center side.

The compression chamber 34 communicates with the discharge port 311 a at the central portion of the fixed scroll 31. A muffler 35 having a discharge hole 351 is provided on the surface of one end side U of the fixed scroll 31. On the surface of one end side U of the muffler 35, a discharge valve 36 is provided which opens and closes the discharge hole 351 in a predetermined manner to prevent the backflow of the refrigerant. Therefore, the refrigerant compressed in the compression chamber 34 is discharged to the discharge space 91 in the upper shell 12 from the discharge hole 351 by opening the discharge valve 36 by the pressure via the discharge port 311 a. Thereafter, the discharged refrigerant flows out of the discharge pipe 15.

The refrigerant is made of, for example, a halogenated hydrocarbon having a carbon double bond, a halogenated hydrocarbon having no carbon double bond, a hydrocarbon, or a mixture containing them in the composition.

The refrigerant composed of a halogenated hydrocarbon having a carbon double bond is an HFC refrigerant or a fluorocarbon-based low GWP refrigerant having an ozone layer destruction coefficient of zero. Examples of these refrigerants include tetrafluoropropenes such as HFO 1234yf, HFO 1234ze, HFO 1243zf, and the like, represented by the chemical formula C ₃ H ₂ F ₄ .

The refrigerant which consists of a halogenated hydrocarbon which does not have a double bond of carbon is exemplified by a refrigerant in which R32 (difluoromethane) represented by CH ₂ F ₂ , R 41 and the like are mixed.

Examples of the refrigerant composed of hydrocarbons include propane and propylene which are natural refrigerants.

Examples of the refrigerant composed of a mixture include mixed refrigerants in which R32, R41 and the like are mixed with HFO1234yf, HFO1234ze, HFO1243zf and the like.

Among the potential low GWP refrigerants, such as propane or propylene, which are components such as HFO 1234yf, HFO 1234ze, HFO 1243zf, operate at relatively low pressure and low density. For this reason, the displacement volume of the compressor required to obtain the equivalent capacity is about two to three times as large as that of the current refrigerant such as R410A.

The drive mechanism 4 is provided on the other end L of the main frame 2 in the shell 1. The drive mechanism unit 4 includes a stator 41 and a rotor 42.

The stator 41 is an annular stator. The stator 41 is formed by arranging a plurality of teeth, in which a winding is wound around an iron core in which a plurality of electromagnetic steel sheets and the like are laminated, with an insulating layer interposed therebetween. The stator 41 is fixedly supported in the main shell 11 by shrink fitting.

The rotor 42 is disposed in the internal space of the stator 41. That is, the rotor 42 is a cylindrical rotor disposed in a central hole formed inside the stator 41 which is an annular stator. The rotor 42 incorporates a permanent magnet in an iron core on which a plurality of electromagnetic steel sheets and the like are stacked. At the center of the rotor 42, a through hole penetrating in the vertical direction is formed.

The sub frame 5 is a metal frame. The sub frame 5 is provided on the other end side L of the drive mechanism 4 in the shell 1. The sub-frame 5 is fixedly supported on the inner peripheral surface portion of the other end side L of the main shell 11 by shrink fitting, welding or the like. The sub frame 5 includes a sub bearing 51 and an oil pump 52.

The sub bearing portion 51 is a ball bearing provided on the central portion upper side of the sub frame 5. At the center of the sub bearing portion 51, a hole penetrating in the vertical direction is formed.

The oil pump 52 is provided below the central portion of the sub frame 5. The oil pump 52 is disposed by immersing at least a part of the lubricating oil stored in the oil reservoir in the lower shell 13.

The drive shaft 6 is a long metal rod member. The drive shaft 6 is provided in the shell 1. The drive shaft 6 includes a main shaft portion 61, an eccentric shaft portion 62, and an oil passage 63.

The main spindle 61 is an axis that constitutes a main part of the drive shaft 6. The central axis of the main shaft portion 61 is arranged to coincide with the central axis of the main shell 11. The rotor 42 is contact-fixed to the outer surface of the main shaft portion 61.

The eccentric shaft 62 is provided on one end side U of the main shaft 61. The central axis of the eccentric shaft portion is eccentric to the central axis of the main shaft portion 61.

The oil passage 63 is vertically penetrated in the main shaft portion 61 and the eccentric shaft portion 62.

One end side U of the main shaft portion 61 in the drive shaft 6 is inserted into the main bearing portion 22 of the main frame 2. Further, the other end side L of the main shaft portion 61 in the drive shaft 6 is inserted into and fixed to the sub bearing portion 51 of the sub frame 5. Thus, the eccentric shaft portion 62 is disposed in the cylinder of the cylindrical portion 323. Further, the outer circumferential surface of the rotor 42 fixed in contact with the main shaft portion 61 and the inner circumferential surface of the stator 41 maintain a predetermined gap.

A first balancer 64 is provided in the middle of one end side U of the main shaft portion 61. A second balancer 65 is provided midway on the other end side L of the main shaft portion 61. The first and

second balancers

64 and 65 cancel out the unbalanced state due to the rocking motion of the rocking scroll 32.

The bush 7 is a connection member that connects the swing scroll 32 and the drive shaft 6. The bush 7 is made of metal such as iron. The bush 7 is composed of two parts. The bush 7 includes a slider 71 and a balance weight 72.

The slider 71 is a cylindrical member having a weir extending outward. The slider 71 is fitted into each of the eccentric shaft portion 62 and the cylindrical portion 323.

As shown in FIG. 2, the balance weight 72 is a doughnut-shaped member provided with a weight portion 721. The shape viewed from one end side U of the weight portion 721 is a substantially C shape. The balance weight 72 is provided eccentrically with respect to the rotation center in order to offset the centrifugal force of the oscillating scroll 32. The balance weight 72 is fitted to the wedge of the slider 71 by a method such as shrink fitting.

The power supply unit 8 is a power supply member that supplies power to the scroll compressor 100. The feeding portion 8 is formed on the outer peripheral surface of the main shell 11. The feeding unit 8 includes a cover 81, a feeding terminal 82, and a wire 83.

The cover 81 is a cylindrical member that has a cylindrical shape that attaches the bottom to the outer wall surface portion of the main shell 11 and is formed with an opening facing the bottom at a part away from the main shell 11.

The feed terminal 82 is made of a metal member. One of the feed terminals 82 is provided in the cover 81. In addition, the other of the feed terminals 82 is provided in the shell 1. That is, the feed terminal 82 is provided to penetrate the shell 1 by connecting one to the other.

One end of the wiring 83 is connected to the feed terminal 82. In addition, the other of the wires 83 is connected to the stator 41. That is, the wiring connects one side to the other side to supply power to the stator 41 from the power supply terminal 82.

<Relationship between Shell 1 and Compression Mechanism 3>
FIG. 3 is a dashed-dotted line in FIG. 1 in which the circumference of the upper shell 12 according to the first embodiment of the present invention quantifies the shape change of the main shell 11 and the first circular base plate 311 of the fixed scroll 31 after welding. It is an enlarged view showing field A.

As shown in FIG. 3, the main shell 11 has a first inner wall surface portion 111 which is a thin wall portion, a first projecting portion 112 which is a thick wall portion, and a first positioning surface 113.

The first inner wall surface portion 111 is formed to be thin-walled by widening the inner diameter by the length as it is from the first protrusion 112. The first inner wall surface portion 111 is continuously formed on one end side U of the first projecting portion 112.

The first protrusion 112 projects from the first inner wall surface portion 111 to the inner diameter side with the outer diameter as it is. The first projecting portion 112 is continuously formed on the other end side L of the first inner wall surface portion 111.

The first positioning surface 113 is a surface facing the one end side U of the first projecting portion 112 at the boundary between the first projecting portion 112 and the first inner wall surface portion 111. The first positioning surface 113 positions the fixed scroll 31.

That is, the main shell 11 is provided with a step-like portion whose inner diameter increases toward the other end side L. The fixed scroll 31 is fixed to the first inner wall surface portion 111 by shrink fitting in a state where the fixed scroll 31 is positioned by the first positioning surface 113.

On the other hand, as shown in FIG. 3, the fixed scroll 31 has a mounting end 313, an annular protrusion 314, and a small diameter end 315.

The placement end 313 is placed on the first positioning surface 113 which is a boundary between the first protrusion 112 and the first inner wall surface 111. The placement end portion 313 is a corner portion on the other end side L of the outer peripheral portion of the fixed scroll 31.

The annular protrusion 314 has a diameter larger than the placement end 313 and contacts the inner wall portion of the first inner wall surface portion 111. The annular protrusion 314 is the outermost diameter portion of the outer peripheral portion of the fixed scroll 31. The annular protrusion 314 is formed separately from the mounting end 313. The annular protrusion 314 is formed in a curved shape between one end U and the other end L in the axial direction of the main shell 11. That is, the annular protrusion 314 has an arc shape. The annular protrusion 314 has an apex 314 A at which the outer radius of the outer circumferential surface of the first circular base plate 311 is maximized. The apex 314A of the annular protrusion 314 is designed to coincide with the height position of 1/2 of the circular base plate thickness t. The annular protrusion 314 is formed in a circular arc shape that is line-symmetrical to one end U and the other end L with reference to the vertex 314A.

The small diameter end 315 is smaller in diameter than the annular projection 314 at the opposite side of the placement end 313 via the annular projection 314. The small diameter end portion 315 is a corner portion on one end side U of the outer peripheral portion of the fixed scroll 31.

The mounting end 313, the annular protrusion 314 and the small diameter end 315 are provided on the mounting protrusion 316. The mounting protrusion 316 protrudes radially outward from the base of the first circular base plate 311 of the fixed scroll 31. The placement protrusion 316 can also be said to be part of the first circular base plate 311.

Thus, the structure in which the fixed scroll 31 is fixed alone to the main shell 11 eliminates the need for a wall for bolting the main frame and the fixed scroll as in the prior art. That is, the wall portion of the main frame 2 is not interposed between the outer peripheral surface of the second circular base plate 321 of the oscillating scroll 32 and the inner wall surface of the main shell 11. As a result, the outer circumferential surface of the second circular base plate 321 and the inner wall surface of the main shell 11 are arranged to face each other. Therefore, the suction space 92, which is a refrigerant intake space provided in the main shell 11 between the first circular base plate 311 of the fixed scroll 31 and the thrust bearing of the main frame 2, and in which the oscillating scroll 32 is disposed is It is spread more than. Further, since the structure of the main frame 2 is simplified, the processability is improved and the weight can be reduced.

The expansion of the suction space 92 provides various advantages. For example, in a so-called low pressure shell structure in which the pressure in the space inside main shell 11 in which drive mechanism 4 is disposed and suction space 92 is lower than the pressure in suction space 92, rocking scroll 32 is generated by the pressure of the compressed refrigerant. The second circular base plate 321 is pressed against the thrust plate 24. Therefore, a thrust load is generated at the sliding portion. Therefore, the diameters of the second circular base plate 321 and the thrust plate 24 of the rocking scroll 32 can be increased while the first and second spiral bodies and the like are designed as in the conventional design, and the sliding area is increased. Contact pressure can be reduced. Therefore, in the scroll compressor 100, the load on the thrust bearing is reduced, and the reliability is enhanced.

Further, at the time of manufacturing and assembly, the upper shell 12 before the circumference is welded presses the fixed scroll 31 against the first positioning surface 113, so that the fixed scroll 31 can be accurately positioned. Thereafter, once the upper shell is removed, the fixed scroll shrink fit is performed.

The main frame 2 is positioned by the second positioning surface 115 facing the one end side U of the second projecting portion 114 which protrudes from the first projecting portion 112 of the main shell 11 to the inner diameter side without changing the outer diameter. Then, the main frame 2 is fixed to the first protrusion 112 by shrink fitting or the like in a state of being positioned by the second positioning surface 115.

At an outer peripheral end of the flat surface 212 of the main frame 2, an annular protruding wall portion 216 protruding to one end side U is formed. The thrust plate 24 is disposed on the inner flat surface 212 of the projecting wall portion 216 so as to cover a portion of the first Oldham groove 215. The height from the flat surface 212 of the projecting wall portion 216 is set smaller than the thickness of the thrust plate 24. For this reason, the oscillating scroll 32 slides on the thrust plate 24.

In addition, if the thickness of the thrust plate 24 is adjusted, the spiral tip clearance which is the distance between the surface of the first and second

circular base plates

311 and 321 having the spiral body and the tip of the other spiral body. Can be set in a preferred range. The spiral tip clearance can be reduced, and the refrigerant can be prevented from leaking to the adjacent compression space through the clearance between the spiral tip and the circular base plate.

Here, a convex portion or a concave portion is formed on the thrust plate 24 and the projecting wall portion 216, and the convex portion and the concave portion are engaged so that the rotation of the thrust plate 24 can be suppressed. This is because the flat surface 212 of the main frame 2 and the thrust plate 24 are both ring-shaped, so the thrust plate 24 may rotate relative to the flat surface 212 as the swing scroll 32 swings. It is. The rotation of the projection is suppressed by locking the projection to the recess.

Here, the projections are a pair of projections 217 formed to project from the projecting wall portion 216 in the direction of the thrust plate 24. The recess is a notch 241 formed in the outer peripheral edge portion of the thrust plate 24. The pair of protrusions 217 is locked to each of both side edges of the notch 241.

A suction port 213 is disposed in a portion located between the pair of protrusions 217 of the main frame 2. That is, since the suction port 213 is disposed at the notch 241, the refrigerant can be taken into the suction space 92 without being blocked by the thrust plate 24.

<Operation of Scroll Compressor 100>
When the feed terminal 82 of the feed unit 8 is energized, torque is generated in the stator 41 and the rotor 42, and the drive shaft 6 rotates accordingly. The rotation of the drive shaft 6 is transmitted to the oscillating scroll 32 via the eccentric shaft portion 62 and the bush 7. The swing scroll 32 to which the rotational drive force is transmitted is restricted in rotation by the Oldham ring 33, and eccentrically revolves with respect to the fixed scroll 31. At that time, the other surface of the oscillating scroll 32 slides on the thrust plate 24.

The refrigerant drawn into the shell 1 from the suction pipe 14 along with the rocking motion of the rocking scroll 32 reaches the suction space 92 through the suction port 213 of the main frame 2, and the fixed scroll 31 and the rocking scroll And 32 into the compression chamber 34. Then, the refrigerant is reduced in volume and compressed in the compression chamber 34 moving from the outer peripheral portion toward the center along with the eccentric revolution movement of the oscillating scroll 32. At the time of eccentric revolution operation of the rocking scroll 32, the rocking scroll 32 moves radially outward with the bush 7 by its own centrifugal force, and the wall surfaces of the second spiral body 322 and the first spiral body 312 are in close contact with each other. The compressed refrigerant travels from the discharge port 311 a of the fixed scroll 31 to the discharge hole 351 of the fixed scroll 31, opens the discharge valve 36 against the biasing force of the discharge valve 36, and flows out of the shell 1.

<Method of Storing Compression Mechanism 3 in Main Shell 11>
FIG. 4 is an explanatory view showing the wall surface portion of the main shell 11 according to Embodiment 1 of the present invention in a longitudinal cross section. FIG. 4 shows the size, thickness, and the like of the main shell 11 before the fixed scroll 31, the main frame 2, the stator 41, etc. are shrink fitted.

The thickness of the main shell 11 is, for example, 4 to 6 mm. The height of the second protrusion 114, that is, the cutting depth by cutting is, for example, about 0.3 mm. Next, the wall surface portion is cut by a predetermined depth in the thickness direction with a cutting brush or the like at the first protrusion 112 separated by a predetermined distance from the second protrusion 114 toward the one end U. Thus, the first inner wall surface portion 111 is formed, and a step is formed at the boundary between the first inner wall surface portion 111 and the first projecting portion 112. Therefore, the inner diameter R1o of the first inner wall surface portion 111 is larger than the inner radius R20 of the first projecting portion 112. The second protrusion 114 may be formed after the first protrusion 112 is formed.

An outer diameter process is performed on the connection portion of the first protrusion 112 with the first inner wall surface portion 111, that is, the portion on the first inner wall surface portion 111 side of the first positioning surface 113 by a rhombic insert or the like. A recess 1131 is formed. Further, the connecting portion of the second protrusion 114 with the first protrusion 112, that is, the portion of the second positioning surface 115 on the side of the first protrusion 112 is subjected to an outer diameter process with a rhombic insert or the like, A recess 1151 recessed in L is formed.

The

depressions

1131 and 1151 are so-called nasumi that prevent deformation of the main shell 11 that is likely to occur in the connection portion due to cutting. That is, as a result of cutting, the connection between the first inner wall surface portion 111 and the first positioning surface 113 may not be finely cut at a right angle, and a convex portion may be formed at a corner. If a convex portion is formed in the portion, even if the fixed scroll 31 is disposed on the first projecting portion 112, the fixed scroll 31 floats without contacting the first positioning surface 113, and the positioning accuracy is lowered. . On the other hand, since the fixed scroll 31 reliably contacts the first positioning surface 113 by forming the recess 1131, the positioning accuracy is enhanced. The same applies to the recess 1151 and the positioning accuracy of the main frame 2 is enhanced.

In addition, since the

recesses

1131 and 1151 have a shape which is recessed on the other end side L, reduction in thickness of the main shell 11 can be suppressed as compared with the case where the

recesses

1131 and 1151 are formed in the thickness direction of the main shell 11, A reduction in strength of the main shell 11 can be suppressed.

Next, the main frame 2 is inserted from one end side U of the main shell 11 formed as described above. The main frame 2 is in surface contact with the second positioning surface 115, and the height direction is positioned. In that state, the main frame 2 is fixed to the first protrusion 112 by shrink fitting or arc spot welding.

Then, the drive shaft 6 is inserted into the shaft hole 221 of the main frame 2. Thereafter, the bush 7 is attached to the eccentric shaft 62. Furthermore, the Oldham ring 33, the oscillating scroll 32, etc. are arranged.

Next, the fixed scroll 31 is inserted from one end side U of the main shell 11. The fixed scroll 31 is in surface contact with the first positioning surface 113, and the height direction is positioned.

There is no member like the conventional bolt for positioning the fixed scroll 31 in the circumferential direction. Therefore, the fixed scroll 31 can rotate with respect to the oscillating scroll 32 until the fixed scroll 31 is fixed. As a result, the positional relationship between the first spiral body 312 and the second spiral body 322 is shifted, and there is a possibility that compression variation or compression failure may occur in each of the scroll compressors 100. Therefore, the fixed scroll 31 is rotated so that the positional relationship of the first scroll 312 with respect to the second scroll 322 of the oscillating scroll 32 becomes a predetermined relationship, and the phase of the fixed scroll is adjusted. Thereafter, the fixed scroll 31 is fixed to the first inner wall surface portion 111 by shrink fitting.

In this step, the fixed scroll 31 is inserted so as to press the first positioning surface 113 by the upper shell 12. Then, the upper shell 12 is once removed. Then, the fixed scroll 31 is maintained in a state of being pressed against the first positioning surface 113, and the fixed scroll 31 is shrink-fitted and fixed to the main shell 11. Thereby, the variation in the height of the suction space 92 for each scroll compressor 100 is suppressed, and the positional accuracy is enhanced. Further, the displacement of the fixed scroll 31 in the vertical direction when the scroll compressor 100 is driven is suppressed. However, as long as the first positioning surface 113 can only position the fixed scroll 31 during manufacture, the fixed scroll 31 contacts the first positioning surface 113 after the fixed scroll 31 is fixed to the first inner wall surface portion 111. It is not necessary to The same applies to the relationship between the main frame 2 and the second positioning surface 115.

Finally, the upper shell 12 is inserted from one end side U of the main shell 11. Thereafter, the circumference of the upper shell 12 is fixed to the main shell 11 by welding.

<Center of Load on Outer Surface of Fixed Scroll in Conventional Comparative Example>
Here, when the fixed scroll 31 is fixed to the first inner wall surface portion 111 of the main shell 11 by shrink fitting, the welded portion where the upper shell 12 is welded to the main shell 11 shrinks after cooling. Then, a force is caused to contract on the outer peripheral portion on the one end side U of the main shell 11, and the first circular base plate 311 of the fixed scroll 31 to be shrink fitted is compressed. Since a surface pressure distribution is generated on the outer peripheral surface of the first circular base plate 311, a bending moment acts on the outer peripheral surface of the first circular base plate 311 and is formed on the first circular base plate 311 and the other end side L thereof. There is a problem that the first spiral body 312 is deformed.

FIG. 5 is an explanatory view showing a measurement range regarding the shape change of the main shell 11 after welding and the first circular base plate 311 of the fixed scroll 31 in the comparative example. FIG. 6 is a diagram showing the amount of change in shell shape with respect to the shape change of the main shell 11 after welding and the first circular base plate 311 of the fixed scroll 31 in the comparative example. FIG. 7 is a view showing the surface pressure of the outer peripheral surface of the circular base plate in relation to the shape change of the main shell 11 after welding and the first circular base plate 311 of the fixed scroll 31 in the comparative example. .

As shown in FIG. 6, the outer radius of the main shell 11 was substantially uniform regardless of the height direction in the original state of (1). If the circumference of the upper shell is welded without a circular base plate as in (2) from the state of (1), the measurement point that is the upper end of the one end side U of the main shell 11 near the weld position 121 of the circumference On a height 0 basis, the outer radius shrinks about 0.1% as shown by the shrinkage amount dR. As a result, the outer radius of the first inner wall surface portion 111 increases in proportion to the height, and the area of the first protrusion 112 returns to the original uniform state.

On the other hand, once the outer peripheral surface of the main frame 2 is shrink-fit to the first projecting portion and the outer peripheral surface of the first circular base plate 311 of the fixed scroll 31 is shrink-fitted to the first inner wall surface portion 111 The outer radius expands and expands in the outer peripheral surface height range of the circular base plate as in (3). Next, when the circumference of the upper shell is welded as in (4) from the state of (3), the height of the main shell 11 is measured at the height of 0 measurement point which is the upper end of the one end side U of the main shell 11 The outer radius shrinks by about 0.1%.

As shown in (4), the main shell 11 is deformed so as to expand under the influence of the outer peripheral surface of the first circular base plate 311 of the fixed scroll 31, and then inclined so as to contract the one end side U as a whole. At this time, on the outer peripheral surface of the first circular base plate 311, the other end side L from the center is deformed so as to be the apex 314A which is the outermost diameter. Therefore, a substantially trapezoidal surface pressure load distribution as shown in FIG. 57 acts on the outer peripheral surface of the first circular base plate 311.

Since the outer radius of the main shell 11 shrinks in proportion to the height direction as shown in (2) of FIG. 6 when there is no first circular base plate 311, the outer radius of the outer peripheral surface of the first circular base plate 311 The surface pressure load also changes substantially proportionally in the height direction. Thus, the position of the center of gravity of the surface pressure distribution load is in the range of 1/3 to 1/2 of the thickness t from the corner portion 311X on one end side U of the outer peripheral surface of the first circular base plate 311 to the other end side L. It is a height position.

On the other hand, the first circular base plate 311 of the fixed scroll 31 has a bending moment acting around the neutral surface of the thickness t cross section, and is deformed axially symmetrically so that the center is bent concavely toward the other end side L. Assuming that the bending moment M per unit length, the moment of inertia I (= t3 / 12), and the bending rigidity D of the plate according to the reference document 1,
M = D (1 + ν) / ρ
It is.

Here, the neutral surface coincides with the center of gravity of the circular base plate, and substantially coincides with the height position of 1/2 of the circular base plate thickness t.

Reference 1 (Kazuo Terasawa, Yoshikazu Matsuura "Mechanics of Materials (Upper Volume)" pp. 86-89, 115-117, 219-224 (issued at 7th edition of 1984, Kaibundo)) Explain about However, assuming that the three-dimensional deformation in the x, y, and z directions is also approximately affected by the Poisson's ratio ν, the displacement in the z direction is expressed as the moment of inertia I of the two-dimensional zx cross section. Match the deflection.

The maximum bending stress σmax acting on the upper and lower surfaces of the first circular base plate 311 fixedly supporting the outer peripheral portion is
σmax = 6 M / t2
And agree with the maximum bending stress of the deflection of the beam.

Further, the deflection amount of the first circular base plate 311 can be obtained by the equation (5.21) of P226 of the reference document 1.

On the other hand, the gravity center position 311G of the first circular base plate 311 is a height position of 1/2 of the circular base plate thickness t. The center of gravity position 311 G of the first circular base plate 311 in the axial direction of the main shell 11 is within the range of the annular protrusion 314. The deviation between the gravity center position 311G of the first circular base plate 311 and the gravity center position of the surface pressure load acts on the outer peripheral surface of the first circular base plate 311 as a bending moment around the gravity center. That is, the load in the hatched portion shown in FIG. 7 acts on the t / 6 shift from the gravity center position 311G of the first circular base plate 311 to deform the first circular base plate 311 in a concave shape toward the other end L Creates a bending moment.

<Loading Center of Outer Surface in Embodiment 1>
FIG. 8 is an explanatory view showing a measurement range regarding the shape change of the main shell 11 after welding and the first circular base plate 311 of the fixed scroll 31 according to the first embodiment of the present invention is there. FIG. 9 shows the amount of change in shell shape with respect to the shape change of the main shell 11 and the first circular base plate 311 of the fixed scroll 31 after welding, according to the first embodiment of the present invention. FIG.

The shape change of (1) to (4) in the height direction of the outer radius of the main shell 11 shown in FIG. 9 is substantially the same change as in FIG. 6 of the comparative example, and the detailed description is omitted. That is, as in the comparative example, when the circumference of the upper shell 12 of (4) is welded, the main shell 11 has the outer radius at the measurement point height 0 reference 110 which is the upper end of the one end side U Shrinks by about 0.1% to 0.2% indicated by the shrinkage amount dR. Then, in the outer peripheral surface height range of the circular base plate on the other end side L in the main shell 11, it is deformed so as to bulge outward.

A chevron arc shape is formed on the outer peripheral surface of the first circular base plate 311, with the point where the outer radius is maximum as the vertex 314A, and the first one is near the vertex which is the position from the one end side U to the axis height position Z1A. Contact with the inner wall portion 111. The contraction amount dR is about 0.1% of R10. The amount of contraction at position Z1A is about 20% to 50% of R10. In this case, the inclination angle θ1 of the first inner wall surface portion 111 of the main shell 11 shown in FIG.
The inclination angle θ1 = dR / Z1A = 1/500 to about 1/200.

Even if the main shell 11 inclines, the position where the surface pressure load acts is in the range of the inclination angle θ1 of the chevron, and does not move significantly from the vicinity of the vertex 314A. Therefore, the outer peripheral surface of the first circular base plate 311 is designed to be designed at the barycentric position 311G of the first circular base plate 311 where the apex 314A position of the chevron arc coincides with the height position of 1/2 of the circular base plate thickness t. There is no large bending moment around the center of gravity. Thereby, the deformation of the first circular base plate 311 and the deformation of the first spiral body 312 formed on the other end side L of the first circular base plate 311 are suppressed.

<Pressure and seal condition>
Next, using FIG. 3, the results of quantitatively examining the shape change of the main shell 11 and the first circular base plate 311 will be described.

In the inner space of the shell 1, a discharge space 91 for guiding the high pressure refrigerant of the discharge pressure Pd compressed by the compression chamber 34 to the discharge pipe 15 is formed on one end side U of the fixed scroll 31 from the first circular base plate 311. It is done. Near the center of the discharge space 91, a muffler 35 and a discharge valve 36 are attached.

On the other hand, on the other end side L from the first circular base plate 311 of the fixed scroll 31, the compression chamber 34 surrounded by the first spiral body 312 and the second spiral body 322 and the suction pressure Ps connected to the suction pipe 14 A suction space 92, which is a low pressure refrigerant intake space, is formed.

The first circular base plate 311 of the fixed scroll 31 is pressed from the one end side U to the other end side L by the pressure difference between the two spaces which are the discharge space and the refrigerant intake space. Therefore, the other end side L of the outer peripheral surface of the first circular base plate 311 is pressed against the first positioning surface 113, and an annular seal surface 317O is formed.

Furthermore, on the outer peripheral surface of the first circular base plate 311, there is a vertex 314A which is an outermost diameter portion in a mountain arc region ta ranging from the end 314X on one end U to the end 314Y on the other end L. . The vicinity of the apex 314A is pressed against the first inner wall surface portion 111 in the other end L direction by the above-described differential pressure, and a sealing surface 317A is formed annularly.

On the outer peripheral surface of the first circular base plate 311, the discharge space 91 at one end side U of the seal surface 317A, which is a contact point contacting the first inner wall surface portion 111 of the annular protrusion 314, is in a high pressure state of the discharge pressure Pd. On the other hand, the other end L from the sealing surface 317O is in a low pressure state of the suction pressure Ps. A gap between the seal surface 317A and the other end L of the seal surface 317A and the one end U of the seal surface 317O is an intermediate pressure state between the low pressure state and the high pressure state. More specifically, this gap is close to a high pressure state because the seal area of the seal surface 317O is dominant.

The fixed scroll 31 has the first scroll 312 and the muffler 35 on the center side, so the rigidity of the inner region is higher than the rigidity of the outer region than the first scroll 312. Further, the inner region of the first circular base plate 311 of the fixed scroll 31 is a compression chamber 34 in which the refrigerant is boosted from the suction pressure Ps to the discharge pressure Pd. In the compression chamber 34, the differential pressure with the discharge pressure Pd of the discharge space 91 at the one end side U is small.

Here, the inner radius of the region inward of the first scroll body 312 from the central axis of the scroll compressor 100 is taken as Rb. Similarly, let the inner radius up to the first protrusion 112 of the main shell 11 be Ra.

<Maximum load pressure condition>
As a calculation model similar to the pressure load conditions described above, reference document 2 (Japanese Society of Mechanical Engineers, "Mechanical Engineering Handbook A4 Material Mechanical Fundamentals", pp. 57-58 (issued 9th edition of 2001 New Edition, Maruzen)) is used. The amount of deformation of the first circular base plate 311 is predicted using a calculation model in which a pressure distribution acts on a circular ring plate having an inner peripheral movable piece from Reference Document 2.

In the vapor compression refrigeration cycle, assuming a maximum load pressure condition (Pd = 3.8 MPa, Ps = 1 MPa) using R410A refrigerant as a typical design operation condition, the differential pressure ΔP is Pd−Ps = 2. Assuming that 8 MPa acts from one end U to the other end L, the amount of deflection of the first circular base plate 311 due to the differential pressure (Pd−Ps) load is determined.

Assuming that the dimensions of the first circular base plate 311 are thickness t = 20 mm, Ra = 80 mm, Rb = 48 mm (Rb / Ra = 0.6), the range from the outermost diameter R1 to Rb of the first circular base plate 311 A load of differential pressure ΔP works in the lower side of the axial center of the drive shaft 6 in the outer peripheral area of the drive shaft 6. Assuming that the material of the first circular base plate 311 is cast iron, it has a Young's modulus of 100 GPa and a Poisson's ratio of 0.3.

<Necessary shrink fit>
A fixed holding force Ff acts on the outer peripheral surface of the first circular base plate 311 by shrink fitting to the first inner wall surface portion 111 of the main shell 11.

The fixed holding force Ff is the rotational direction gas torque Ft1 at the time of compression operation, the thrust reaction force Ft2 received from the compression chamber 34 at the time of activation, and pressure applied to the suction space 92 with the discharge space 91 evacuated in unsteady state. Overcoming the thrust reaction force Ft3, the fixed scroll 31 is fixedly held.

Among them, the largest one is the thrust reaction force Ft3 in the unsteady state. Assuming that the reverse pressure applied to the suction space 92 is Ps (= 1 MPa),
Thrust reaction force Ft3 = π (Ra) ² × Ps = 20 kN
It is.

And
Fixed holding force Ff = static friction coefficient μ × clamping force Fin> Ft3
It is.

To obtain a fixed holding force Ff larger than the thrust reaction force Ft, with μ = 0.5,
Tightening force Fin> Ft 3 / static friction coefficient μ
It is.

As a result, the tightening force Fin is 40 kN or more, and the shrink fitting margin is 0.1 mm or more, that is, 0.13% or more of the inner diameter Ra.

Furthermore, when the circumference of the upper shell 12 is welded to the main shell 11, the main shell 11 is deformed to about 0.1 mm which is a contraction amount dR of the main shell 11 and about 1/500 to 1/200 which is an inclination angle θ1. .

<The amount of deflection due to the differential pressure of the simple support disc circular base plate>
On the other hand, when the differential pressure ΔP (= 2.8 MPa) acts under the maximum load operating condition at the time of compression operation, No. 1 Applying the calculation model of 15 (ring plate, outer circumferential simple support, fixed to inner circumferential movable piece, equal distribution load), at the position of radius Rb of the inner circumferential movable piece,
Maximum deflection w_max = α × ΔP × (Ra) ⁴ / t3 = 7 μm
It becomes.

Since the outer peripheral surface of the circular base plate of the outer peripheral simple support is not restrained, that is, the bending moment Mr = 0, it bends and tilts. The inclination angle is 3 / 10,000. The amount of change in outer peripheral surface outer diameter (= thickness t × inclination angle) of the first circular base plate 311 at this time is 6 μm. Therefore, the inclination is negligible compared to about 1/500 to 1/200 which is the inclination angle θ1 of the outer peripheral surface of the main shell due to welding of the shrinkage fit and the circumference.

Hereinafter, when the first circular base plate 311 is fixedly supported on the first inner wall surface portion 111 of the main shell 11 deformed by the shrinkage fit and welding of the circumference, a bending moment Mr is acting on the outer peripheral surface Think and predict the amount of deformation.

<The amount of deflection due to the differential pressure of the fixed support circular base plate>
Next, No. When the bending moment Mr1 due to the upper and lower differential pressure load is calculated from the calculation model of 16 (ring plate, outer peripheral fixed support, fixed to inner peripheral movable piece, equal distribution load), at the position of radius Rb of the inner peripheral movable piece,
Maximum deflection w_max = α × ΔP × (Ra) ^{4 /} t ³ = 1.4 μm
It is.

The deflection angle is zero.

The maximum stress is
Maximum stress | σ_max | = β × ΔP × (Ra) ² / t ²
It is.

The bending moment is
Bending moment Mr1 = | σ_max | / section coefficient Z
= Β × π × △ P × (Ra) 3/3, ( wherein, when Rb / Rb = 0.6, a beta = 0.25.)
= 375 Nm
It becomes.

On the outer peripheral surface of the first circular base plate 311 fixed to the main shell 11, the bending moment Mr1 due to the upper and lower differential pressure load and the height position of the center of the outer peripheral surface load due to contraction after welding at the center of gravity position 311G The bending moment Mr2 works by shifting a predetermined distance from. That is, on the outer peripheral surface of the first circular base plate 311, a bending moment which causes the other end L to be concavely deformed usually acts. The direction in which the other end L is recessed is +. If the bending moment Mr2 is about the bending moment Mr1 due to the upper and lower differential pressure load, the influence on the maximum deflection w_max is similarly 1 to 2 μm level, so it may be ignored small enough.

Next, assuming that the clamping force Fin is (π (Ra) ² × Ps) / μ, the bending moment Mr2 is
Mr2 = dH1 × Fin = dH1 × (π (Ra) ² × Ps) / μ
It becomes.

Here, assuming that Mr2 = Mr1,
dH1 = μ × Mr1 / Ft3
= (Μ × β × π × △ P × (Ra) 3/3) / (π (Ra) 2 × Pm)
= Ra x (μ x β / 3) x (ΔP / Ps)
= Ra x γ
It becomes.

Rb / Ra is usually about 0.6. At this time, β = 0.25 and γ = 6.6%. Furthermore, Rb / Ra is at most about 0.8. When Rb / Ra = 0.8, β = 0.067 and γ = 1.1%.

That is, if the displacement distance dH1 from the center of gravity to the center of gravity is about 1% of Ra, the maximum deflection w_max at the position of the inner diameter Ra is 1 to 2 μm at the same level as the influence by the upper and lower differential pressure It is. As a result, the bending moment Mr2 is considered to be negligible because it is sufficiently small.

Further, in the first embodiment, on the outer peripheral surface of the first circular base plate 311 shown in FIG. 3, only the outermost diameter R1 in the vicinity of the apex 314A which is the outermost diameter contacts the first inner wall surface portion 111. The thickness of the main part of the first circular base plate 311 is t. On the other hand, the width of the side wall near the outer periphery is the thickness of the mounting protrusion 316, and the thickness is smaller than t at t1. The one end side U of the first inner wall surface portion 111 may contact at the small diameter end portion 315 in the vicinity of the apex 314A in order to contract. However, assuming that the outer radius of the small diameter end portion 315 is R2, the outer diameter difference from the apex 314A is e2 = R1-R2, and the difference in height position from the apex 314A is x1A, The contact angle θ2 is
θ22tan (θ2) = e2 / x1A
It becomes.

If e2 is designed to be larger than about 0.1 mm which is the deformation of the end 110 of the one end side U of the main shell 11 after welding of the circumference, the relationship of θ2> θ1 is maintained, and the small diameter end It is possible to prevent the contact between the first and second

inner wall portions

111 and 315.

However, if the relationship of θ1θθ2 can be maintained, even if they are in contact with each other, the tightening force acting at the small diameter end portion 315 is small and can be ignored. Details will be described in Embodiment 2 separately.

On the other hand, at the mounting end 313 which is the corner on the other end L of the outer periphery of the first circular base plate 311, the outer radius is R1o, and the outer diameter difference from the apex 314A is eo = R1-R1o, the apex Assuming that the difference in height position from 314A is y1A, the contact inclination angle θo from the apex 314A to the mounting end 313 is
θo ≒ tan (θo) = eo / y1A
It becomes.

If eo is designed to be larger than about 0.1 mm which is the deformation of the end 110 of the one end side U of the main shell 11 after welding of the circumference, the relationship of θo> θ1L is maintained, and the mounting end In the portion 313, the contact with the first inner wall surface portion 111 of the main shell 11 can be prevented.

The first inner wall surface portion 111 of the main shell 11 shown in FIG. 3 is deformed so that the outer diameter is maximized at the apex 314A, and the inclination angle θ1L of the other end L is the end of the one end U of the main shell 11 The amount of contraction of the portion 110 is increased. Therefore, the inclination angle θ1 of the one end side U becomes large. On the other hand, since the first protrusion 112 is restrained by the main frame 2 and hardly deformed, the inclination angle θ1L of the other end L is small. As a result, normally, the relationship of θ1L <θ1 is established.

Furthermore, in the first embodiment, if the relationship of θ1L <θo can be maintained, the placement end portion 313 can prevent contact with the first inner wall surface portion 111 of the main shell 11. In addition, if the relationship of θo ≒ θ1L can be maintained, even if they are in contact with each other, they can be ignored because the tightening force is small. This will be described separately in Embodiment 3.

<Action and effect>
Similar to the conventional method of connecting the main frame 2 and the fixed scroll 31 with bolts or the like by the above manufacturing method, the positional accuracy of the main frame 2, the fixed scroll 31, and the oscillating scroll 32 is equivalent to While the suction space 92 can be expanded. Moreover, since a bolt etc. are not used for fixation of fixed scroll 31, manufacture can be simplified.

Thus, for example, the diameters of the second circular base plate 321 and the thrust plate 24 of the orbiting scroll 32 can be increased, the sliding area is increased, and the surface pressure due to the thrust load can be reduced. Further, since a wall for fixing the fixed scroll 31 to the main frame 2 is not necessary, the processing time of the main frame 2 can be shortened and the weight can be reduced.

The main shell 11 has a first protrusion 112 and a second protrusion 114 that protrudes from the first protrusion 112 and forms a second positioning surface 115 on which the main frame 2 is positioned. The main frame 2 is fixed to the second positioning surface 115 alone. Therefore, the fixed scroll 31 and the main frame 2 can be fixed to the shell 1 in the same manufacturing process, and the manufacturing can be facilitated.

Thus, when the fixed scroll 31 is fixed to the main shell 11, the first spiral body 312 formed on the first circular base plate 311 of the fixed scroll 31 and the other end L of the first circular base plate 311 is deformed It is possible to suppress a decrease in compressor efficiency without enlarging the tip end leakage gap between the first and second

spiral bodies

312 and 322 without increasing the size. Alternatively, the tip-to-tip leakage gap between the first and

second spirals

312 and 322 is not narrowed, and the tip is not in contact with the wall surface, so that the reduction in durability can be suppressed. Therefore, the displacement volume of the compression chamber 34 can be expanded with the shell diameter equivalent to that of the conventional scroll compressor.

The refrigeration cycle apparatus may further include a scroll compressor 100, a condenser, an expansion valve, and an evaporator, and may be a high-pressure refrigerant including, for example, R32 as the refrigerant. When a high pressure refrigerant including R32 or the like is used, the load on the thrust bearing is increased. However, in the first embodiment, the diameters of the second circular base plate 321 and the thrust plate 24 of the oscillating scroll 32 can be increased, and the sliding area can be increased. Therefore, the load on the thrust bearing can be reduced, and the reliability can be improved.

<Effect of Embodiment 1>
According to the first embodiment, scroll compressor 100 includes main frame 2 slidably holding oscillating scroll 32. The scroll compressor 100 includes a fixed scroll 31 that forms a compression chamber 34 with the oscillating scroll 32. The scroll compressor 100 includes a shell 1 that fixes the fixed scroll 31 separately from the main frame 2. The shell 1 has a cylindrical main shell 11 including a first projecting portion 112 which is a thick portion and a first inner wall surface portion 111 which is a thin portion which is formed to be thinner than the first projecting portion 112. . The fixed scroll 31 has a placement end 313 placed at the boundary between the first protrusion 112 and the first inner wall surface 111. The fixed scroll 31 has an annular protrusion 314 which is larger in diameter than the mounting end portion 313 and which contacts the first inner wall surface portion 111. The fixed scroll 31 has a small diameter end 315 smaller in diameter than the annular projection 314 on the opposite side to the mounting end 313 via the annular projection 314.

According to this configuration, when the end 110 of the first inner wall surface portion 111 of the main shell 11 is welded to the upper shell 12, the inner diameter of the end 110 of the first inner wall surface portion 111 of the main shell 11 is 1% It shrinks about 2% from. At that time, since the fixed scroll 31 has the small diameter end 315, the bending moment received from the end 110 of the first inner wall surface portion 111 where the small diameter end 315 contracts can be reduced. In the first embodiment, in particular, the small diameter end portion 315 does not contact the contracted first inner wall surface portion 111. Therefore, this bending moment disappears. As a result, in the fixed scroll 31 fixed to the main shell 11 by shrink fitting or the like, a surface pressure distribution that increases from the mounting end portion 313 side to the small diameter end portion 315 side does not occur on the outer peripheral surface. A moment does not act to bend the center of the base plate 311 downward. Therefore, the fixed scroll 31 can be disposed in the shell 1 with high positional accuracy, and the tips of the first scroll 312 of the fixed scroll 31 and the second scroll 322 of the oscillating scroll 32 have an appropriate positional relationship. Configured

As a result, without forming a peripheral wall for fixing the fixed scroll 31 to the main frame 2, the fixed scroll 31 has a high positional accuracy within the shell 1, and the shrink fit and the circumference minimize deformation after welding. Can be placed on And the fall of the endurance of the scroll compressor 100 and reliability can be controlled. Further, the leakage loss of the scroll compressor 100 does not increase, and a reduction in the compressor efficiency can be suppressed.

According to the first embodiment, the mounting end 313 and the annular protrusion 314 are formed separately.

According to this configuration, the outer diameter of the mounting end portion 313 can be smaller than the outer diameter of the annular protrusion 314, and the mounting end portion 313 can prevent contact with the first inner wall surface portion 111 of the main shell 11. As a result, excessive deformation of the main shell 11 can be suppressed.

According to the first embodiment, the annular protrusion 314 is formed in a curved shape in the axial direction of the main shell 11.

According to this configuration, the annular protrusion 314 widens the range of contact with the first inner wall surface portion 111 of the main shell 11. Therefore, stress concentration in the contact range can be avoided, and the durability of the first inner wall surface portion 111 of the main shell 11 can be improved.

According to the first embodiment, the center of gravity position 311G of the first circular base plate 311 of the fixed scroll 31 in the axial direction of the main shell 11 is within the range of the annular protrusion 314.

According to this configuration, the deviation between the gravity center position 311G of the first circular base plate 311 and the gravity center position of the surface pressure load acts on the outer peripheral surface of the first circular base plate 311 as a bending moment around the gravity center.

According to the first embodiment, the mounting end portion 313, the annular protrusion 314 and the small diameter end portion 315 are provided on the mounting projection portion 316 which protrudes outward in the radial direction from the first circular base plate 311 of the fixed scroll 31. .

According to this configuration, the contact with the main shell 11 is limited to the mounting protrusion 316 of the fixed scroll 31, and is separated from the first circular base plate 311 of the fixed scroll 31. As a result, excessive deformation of the main shell 11 can be suppressed.

According to the first embodiment, the shell 1 has the upper shell 12 to which the first inner wall surface portion 111 of the main shell 11 is fixed and which closes the opening on the first inner wall surface portion 111 side of the main shell 11. The first inner wall surface portion 111 of the main shell 11 and the upper shell 12 are joined, and the small diameter end portion 315 of the fixed scroll 31 and the first inner wall surface portion 111 are separated.

According to this configuration, the small diameter end portion 315 of the fixed scroll 31 does not contact the first inner wall surface portion 111 even after the circumference of the upper shell 12 is welded. Therefore, the bending moment which the small diameter end portion 315 receives from the first inner wall surface portion 111 where the circumference of the upper shell 12 is contracted after welding is eliminated.

Hereinafter, in the second to fifth embodiments, the parts having the same configuration as the scroll compressor 100 of FIGS. 1 to 6 according to the first embodiment are assigned the same reference numerals and descriptions thereof will be omitted. Further, as in the first embodiment, the effect of enlarging the displacement volume of the compression chamber 34 is achieved while ensuring the improvement of the efficiency and the reliability of the scroll compressor 100. A detailed description of such similar effects is omitted.

Second Embodiment
<When the contact and inclination angle at the small diameter end 315 is θ2θθ1>
FIG. 10 is an alternate long and short dash line in FIG. 1 where the circumference of the upper shell 12 according to the second embodiment of the present invention quantifies the shape change of the main shell 11 after welding and the first circular base plate 311 of the fixed scroll 31. It is an enlarged view showing field A.

The mounting end 313, the annular protrusion 314 and the small diameter end 315 are provided on the mounting protrusion 316. The mounting end 313 and the small diameter end 315 are formed to have substantially the same outer diameter. The annular projection 314 protrudes from the outer circumferential surface between the mounting end 313 and the small diameter end 315 of the mounting projection 316. The mounting end 313 and the annular protrusion 314 are separately provided separately.

The amount of contraction and deformation of the end portion 110 of the one end side U of the main shell 11 after welding is approximately equal to 0.1 to 0.2 mm. As described above, if the inclination angle θ2 is designed to be about θ1, even if the small diameter end portion 315 contacts, the following relationship is established. That is, the clamping force generated at the small diameter end 315 is sufficiently smaller than the clamping force generated at the apex 314 A of the annular protrusion 314.

The position of the apex 314 A of the annular protrusion 314 is substantially equal at the axial height position of the center of gravity position 311 G of the fixed scroll 31 and the drive shaft 6. Therefore, the bending moment around the center of gravity of the first circular base plate 311 is minute. As a result, the influence of the deformation of the first circular base plate 311 and the first spiral body 312 can be ignored small enough.

However, in the second embodiment, there is a defect that the circumference is more easily affected by the variation in the amount of contraction and deformation of the main shell 11 after welding than in the first embodiment. On the other hand, as an advantage, the small diameter end portion 315 can be in contact with the first inner wall surface portion 111 to form the sealing surface 317B. Thereby, the seal area is increased, and the leakage of the refrigerant between the discharge space 91 and the suction space 92 can be prevented. In addition, the bending moment generated due to the pressure distribution of the discharge pressure Pd occurring on the outer peripheral surface of the first circular base plate 311 of the fixed scroll 31 can be eliminated. Normally, the pressure distribution on the outer peripheral surface of the first circular base plate 311 is not a problem. However, it is advantageous when the plate thickness of the first circular base plate 311 is relatively thick, that is, t / R1 is large.

According to the second embodiment, although there is a point that the circumference is more susceptible to the variation of the amount of contraction deformation of the main shell 11 after welding than the first embodiment, it is advantageous depending on the shape of the first circular base plate 311. There is also a good side. And the effect according to Embodiment 1 is acquired.

<Modification 1 of Embodiment 2>
11 quantifies the shape change of the main shell 11 and the first circular base plate 311 of the fixed scroll 31 according to the first modification of the second embodiment of the present invention. It is a figure which shows the state after shrink-fitting. FIG. 12 is an alternate long and short dash line area A of FIG. 1 for quantifying the shape change of the main shell 11 and the first circular base plate 311 of the fixed scroll 31 according to the first modification of the second embodiment of the present invention. The circumference of the figure shows the state after welding.

The mounting end 313, the annular protrusion 314 and the small diameter end 315 are provided on the mounting protrusion 316. The small diameter end 315 is smaller in diameter than the mounting end 313. The annular protrusion 314 is integrally provided with the mounting end 313.

A chevron arc region ta having a vertex 314A is formed on the outer peripheral surface of the mounting protrusion 316. The chevron arc region ta is provided integrally with the mounting end 313 and the annular projection 314. The apex 314 A of the chevron arc region ta is located approximately at the center between the root of the other end side L than the small diameter end 315 and the mounting end 313. That is, the chevron arc region ta is formed in line symmetry at the vertex 314A.

The vicinity of the apex 314 A of the chevron arc region ta contacts the first inner wall surface portion 111 of the main shell 11. In the chevron arc region ta, the other end L from the apex 314 A has an outer diameter dimension as the mounting protrusion 316 from the middle part to the end face of the other end L placed on the first positioning surface 113 The diameter is reduced. The end face on the other end L of the placement protrusion 316 is a part of the annular protrusion 314 and the placement end 313, and is supported by the first positioning surface 113.

If the inclination angle θ2 is designed to be about θ1, even if the small diameter end 315 contacts the first inner wall surface portion 111, the load 319B as the tightening force generated at the small diameter end 315 is the tightening force generated at the apex 314A. It is sufficiently smaller than the main load 319A. The axial height position of the vertex 314A at the drive shaft 6 is substantially equal to the position of the center of gravity position 311G of the fixed scroll 31. Therefore, the bending moment around the center of gravity of the first circular base plate 311 is sufficiently small. As a result, the influence of the deformation of the first circular base plate 311 and the first spiral body 312 can be ignored small enough. Therefore, the effects according to the first embodiment can be obtained.

<Modification 2 of Embodiment 2>
FIG. 13 is a fixed scroll 31 in a dashed dotted line area A in FIG. 1 for quantifying the shape change of the main shell 11 and the first circular base plate 311 of the fixed scroll 31 according to the second modification of the second embodiment of the present invention. It is a figure which shows the state after shrink-fitting. FIG. 14 illustrates the shape change of the main shell 11 and the first circular base plate 311 of the fixed scroll 31 according to the second modification of the second embodiment of the present invention. The circumference of the figure shows the state after welding.

The mounting end 313, the annular protrusion 314 and the small diameter end 315 are provided on the mounting protrusion 316. The small diameter end 315 is smaller in diameter than the mounting end 313. The annular projection 314 is integrally provided with the mounting end 313 and the small diameter end 315.

A chevron arc region ta having an apex 314A is formed on the outer peripheral surface of the annular protrusion 314. The apex 314A of the chevron arc region ta is located on the other end L between the small diameter end 315 and the placement end 313 rather than the center. That is, the chevron arc region ta is formed in a non-linear symmetric shape at the vertex 314A.

One end side U of the chevron arc region ta forms a gentle slope from the vertex 314 A to the small diameter end 315. Here, the point that the inclination angle θ2 is designed to be θ2 ≒ θ1 is the same as that of the first modification of the second embodiment. However, the second embodiment differs from the first modification of the second embodiment in that one end side U of the chevron arc region ta is formed in a gentle slope so as to contact the first inner wall surface portion 111 of the main shell 11. Thus, when the one end side U of the chevron arc region ta contacts the first inner wall surface portion 111 of the main shell 11, the main load 319A as the clamping force of the apex 314A is the load 319C as the clamping force at the contact portion. A maximum load distribution occurs. Here, the axial height position of the vertex 314A at the drive shaft 6 is substantially equal to the position of the gravity center position 311G of the fixed scroll 31. If the inclination angle θ2 can be designed so as to satisfy θ2 ≒ θ1, the effect according to the first embodiment can be obtained.

However, the center of gravity position 311G of the fixed scroll 31 is in the range S of the inclined surface of the one end side U of the angular arc region ta by the way that the inclined surface of the one end side U of the angular arc region ta contacting the first inner wall surface portion 111 contacts. There is a drawback that it can change.

<Effect of Second Embodiment>
According to the second embodiment, the mounting end 313 and the annular protrusion 314 are integrally formed.

According to this configuration, the annular protrusion 314 can be formed large integrally with the mounting end portion 313, and the strength of the annular protrusion 314 can be improved. As a result, the durability of the annular protrusion 314 can be improved.

According to the second embodiment, the shell 1 has the upper shell 12 to which the first inner wall surface portion 111 of the main shell 11 is fixed and which closes the opening on the first inner wall surface portion 111 side of the main shell 11. When the first inner wall surface portion 111 of the main shell 11 is fixed to the upper shell 12, a load 319C as a tightening force which is a bending moment received by the small diameter end 315 of the fixed scroll 31 from the first inner wall surface 111 is fixed scroll. The primary load 319A as a clamping force, which is a bending moment received by the annular projection 314 of 31 in contact with the first inner wall surface portion 111, is smaller.

According to this configuration, the small diameter end portion 315 of the fixed scroll 31 contacts the first inner wall surface portion 111 after the circumference of the upper shell 12 is welded. However, among the bending moments which the small diameter end portion 315 receives from the first inner wall surface portion 111 where the circumference of the upper shell 12 is contracted after welding, the bending moment which the small diameter end portion 315 receives from the first inner wall surface portion 111 The bending moment received in contact with the first inner wall surface portion 111 is smaller. As a result, the influence of the deformation of the first circular base plate 311 and the first spiral body 312 can be ignored small enough. In addition, the small diameter end portion 315 contacts the first inner wall surface portion 111 to form the sealing surface 317B. Thereby, the seal area is increased, and the leakage of the refrigerant between the discharge space 91 and the suction space 92 can be prevented. In addition, the bending moment generated due to the pressure distribution of the discharge pressure Pd occurring on the outer peripheral surface of the first circular base plate 311 of the fixed scroll 31 can be eliminated.

Third Embodiment
<When the contact and inclination angle at the mounting end 313 is θo ≒ θ1L>
FIG. 15 is a dashed-dotted line in FIG. 1 where the circumference of the upper shell 12 according to the third embodiment of the present invention quantifies the shape change of the main shell 11 after welding and the first circular base plate 311 of the fixed scroll 31. It is an enlarged view showing field A.

In the first embodiment, the inclination angle is θ2> θ1 and θo> θ1L. Further, the placement end 313 and the small diameter end 315 do not contact the first inner wall surface 111 of the main shell 11. Then, only the annular protrusion 314 contacts the first inner wall surface portion 111 of the main shell 11.

In the second embodiment, the inclination angle is θ2 ≒ θ1. Further, the mounting end 313 and the small diameter end 315 contact the first inner wall surface 111 of the main shell 11 together with the annular projection 314.

Here, the placement end 313 of the placement protrusion 316 of the first circular base plate 311 contacts the first positioning surface 113 to form an annular seal surface 317O. As the seal width c1 of the seal surface 317O, it is necessary to secure a sufficiently large value of c1 = R1o−Ra obtained by subtracting the inner diameter Ra of the first projecting portion 112 from the inner diameter R1o of the first inner wall surface portion 111. However, in the first embodiment described above, the mounting end 313 does not come in contact with the first inner wall surface 111. For this reason, the size of the seal width c1 is restricted. Further, in the above-described second embodiment, the small diameter end portion 315 contacts the first inner wall surface portion 111. For this reason, there is a drawback that the circumference is easily influenced by the variation in the amount of shrinkage deformation of the main shell 11 after welding.

Therefore, in the third embodiment, in order to secure a sufficient seal area in seal surface 317O, in addition to seal surface 317A in the vicinity of apex 314A, the first inner wall is also provided at mounting end 313 on the other end L than apex 314A. The relationship of θo ≒ θ1L is maintained so as to gently contact the surface portion 111. That is, the mounting end 313 and the annular projection 314 have the same outer diameter. The annular projection 314 is provided by tapering the outer diameter of the mounting projection 316 from the small diameter end portion 315 in the middle. The annular protrusion 314 is slightly reduced in diameter toward the other end L. The mounting end portion 313 is gradually expanded to the same outer diameter as the annular protrusion 314 from the slightly diameter-reduced root on the other end L of the annular protrusion 314.

According to the third embodiment, a value of c1 = R1o−Ra obtained by subtracting the inner diameter Ra of the first projecting portion 112 from the inner diameter R1o of the first inner wall surface portion 111 can be secured sufficiently large as the seal width c1 of the sealing surface 317O. In addition, at the mounting end 313, the amount of contraction and deformation of the main shell 11 after welding is smaller than that of the small diameter end 315, so that the influence of variations becomes difficult.

Fourth Embodiment
<A case where the contact and the inclination angle are θo=θ1L with an annular protrusion having a rectangular cross section including the apex of which the corner is chamfered>
16 is a dashed-dotted line in FIG. 1 where the circumference of the upper shell 12 according to Embodiment 4 of the present invention quantifies the shape change of the main shell 11 after welding and the first circular base plate 311 of the fixed scroll 31. It is an enlarged view showing field A.

In the first embodiment, the annular protrusion 314 has an arc shape formed in a curved shape in the axial direction of the main shell 11, and contacts the first inner wall surface portion 111 near the apex 314A.

In the fourth embodiment, the annular protrusion 314 has a rectangular shape in cross section formed integrally with the placement protrusion 313 on the placement protrusion 316. The placement end 313 is a corner on the other end L of the placement protrusion 316. The rectangular section of the annular protrusion 314 reaching the placement end 313 is chamfered at the corner between the one end U and the other end L. The mounting end portion 313 is chamfered at the corner portion and does not contact the first inner wall surface portion 111 of the main shell 11. The annular protrusion 314 has a length ta between one end U and the other end L. The outer peripheral portion of the annular protrusion 314 is formed in a circumferential surface having a uniform outer diameter in the contact range S. That is, the annular protrusion 314 is linearly formed between the one end U and the other end L in the axial direction of the main shell 11.

Here, when the circumference of the upper shell 12 is welded to the main shell 11, the contraction of the main shell 11 causes the first inner wall surface portion 111 to be inclined and deformed. Next, a vertex 314Ax, which is a first contact point corresponding to a corner of the one end side U of the contact range S in the first inner wall surface portion 111, is also inclined and deformed. At this time, a load distribution like the trapezoidal distribution shown in FIG. 7 occurs. Among the distributed loads, the main load acts in the range from the midpoint position (S / 2) of the contact range S to the one-end side U to S / 6. Therefore, if the position of the gravity center position 311G of the first circular base plate 311 in the fixed scroll is within this range, a large bending moment does not act on the first circular base plate 311. That is, the center-of-gravity position 311G of the first circular base plate 311 in the axial direction of the main shell 11 is within the range of the annular projection 314 and is closer to the one end U than the center of the annular projection 314 in the axial direction of the main shell 11. It is the small diameter end 317 side. As a result, the deformation of the fixed scroll 31 can be kept small.

Furthermore, if the contact range S is sufficiently small, the bending moment acting on the outer peripheral surface of the mounting projection 316 of the fixed scroll 31 can be ignored. If the contact range S is 6% or less of the outermost diameter R1 of the fixed scroll 31, the bending moment becomes a load deflection level at the maximum load operation and can be sufficiently ignored.

According to the fourth embodiment, although the influence of variations in the amount of contraction and deformation of the main shell 11 after welding remains unchanged, the influence of the bending moment can be sufficiently reduced compared to the first embodiment, and according to the first embodiment. An effect is obtained.

<Modification 1 of Embodiment 4>
FIG. 17 is an enlarged view showing a first circular base plate 311 of the fixed scroll 31 according to the first modification of the fourth embodiment of the present invention.

As shown in FIG. 17, the first circular base plate 311 does not have the placement protrusion 316. The fixed scroll 31 is formed with a mounting end 313, an annular protrusion 314 and a small diameter end 315. The mounting end 313 and the annular protrusion 314 are integrally formed. The annular protrusion 314 has the same shape as that of the mounting protrusion 316 of the fourth embodiment. The small diameter end 315 is formed separately from the mounting end 313 and the annular protrusion 314.

<Modification 2 of Embodiment 4>
FIG. 18 is an enlarged view showing a first circular base plate 311 of the fixed scroll 31 according to the second modification of the fourth embodiment of the present invention.

As shown in FIG. 18, the annular protrusion 314 has a rectangular shape in cross section formed integrally with the placement protrusion 313 on the placement protrusion 316. The rectangular section of the annular protrusion 314 is not chamfered at the corner between the one end U and the other end L. The outer peripheral portion of the annular protrusion 314 is formed in a circumferential surface having a uniform outer diameter in a contact range S equal to the thickness.

<Modification 3 of Embodiment 4>
FIG. 19 is an enlarged view showing a first circular base plate 311 of the fixed scroll 31 according to the third modification of the fourth embodiment of the present invention.

As shown in FIG. 19, the annular protrusion 314 has a rectangular shape in cross section formed integrally with the placement protrusion 313 on the placement protrusion 316. The rectangular section of the annular protrusion 314 is not chamfered at the corner between the one end U and the other end L. The outer peripheral portion of the annular protrusion 314 is reduced in diameter toward the mounting end portion 313. The mounting end 313 is smaller in diameter than the annular protrusion 314. For this reason, the placement end 313 does not contact the first inner wall surface portion 111 of the main shell 11.

In the third modification shown in FIG. 19, the position at which the main load 319A works moves to the one end side U as the taper angle for reducing the diameter of the mounting end portion 313 increases. When the working position of the main load 319A moves to one end side U beyond a certain level, the main load 319A can be considered to work at the annular projection 314. Therefore, if the position of the gravity center position 311G of the first circular base plate 311 matches the position of the annular projection 314, a large bending moment that bends the first circular base plate 311 and the first spiral body 312 does not work. As a result, a small deformation state of the fixed scroll 31 can be maintained.

As described above, according to the first to third modifications of the fourth embodiment, although the influence of the variation in the amount of contraction and deformation of the main shell 11 after welding remains, the influence of the bending moment is more sufficient than the first embodiment. It can be made smaller. Therefore, the effects according to the first embodiment can be obtained.

<Effect of Fourth Embodiment>
According to the fourth embodiment, the annular protrusion 314 is formed linearly in the axial direction of the main shell 11.

According to this configuration, the annular protrusion 314 widens the range in contact with the first inner wall surface portion 111 of the main shell 11 over the entire linear region. Therefore, stress concentration in the contact range can be avoided, and the durability of the first inner wall surface portion 111 of the main shell 11 can be improved.

According to the fourth embodiment, the gravity center position 311G of the first circular base plate 311 of the fixed scroll 31 in the axial direction of the main shell 11 is within the range of the annular protrusion 314 and the axis of the main shell 11 of the annular protrusion 314 It is the small diameter end 317 side which is one end side U than the middle in the direction.

According to this configuration, the deviation between the gravity center position 311G of the first circular base plate 311 and the gravity center position of the surface pressure load acts more on the outer peripheral surface of the first circular base plate 311 as a bending moment around the gravity center.

Embodiment 5
FIG. 20 is an enlarged view showing a first circular base plate 311 of the fixed scroll 31 according to Embodiment 5 of the present invention. FIG. 21 is a dashed-dotted line in FIG. 1 where the circumference of the upper shell 12 according to the fifth embodiment of the present invention quantifies the shape change of the main shell 11 after welding and the first circular base plate 311 of the fixed scroll 31. It is an enlarged view showing field A.

In the fourth embodiment, the placement end 313, the annular protrusion 314, and the small diameter end 315 are provided on the placement protrusion 316. The small diameter end portion 315 is formed to have the small diameter projection 315A on the mounting projection 316. The small diameter projection 315A annularly protrudes from the small diameter end 315 radially outward. The small diameter end portion 315 is formed larger in diameter than the mounting end portion 313.

The annular protrusion 314 annularly protrudes radially outward from the mounting protrusion 316. The annular projection 314 is formed larger in diameter than the small diameter projection 315A of the small diameter end portion 315. The annular projection 314 is provided separately from the mounting end 313.

The mounting end 313 is formed at the corner of the mounting protrusion 316 itself. The mounting end 313 has a smaller diameter than the small diameter end 315 having the small diameter projection 315A. For this reason, the placement end 313 does not contact the first inner wall surface portion 111 of the main shell 11.

The outer peripheral portion of the annular protrusion 314 is formed in the shape of a circumferential surface having a uniform outer diameter. Moreover, the outer peripheral part of the small diameter end part 315 is formed in the circumferential surface form with uniform outer diameter. Between the outer peripheral portion of the annular protrusion 314 and the outer peripheral portion of the small diameter end portion 315, a recessed portion 318 having a step is formed. The axial height position of the annular protrusion 314 on the drive shaft 6 is substantially the same as the gravity center position 311 G of the fixed scroll 31.

Here, when the fixed scroll 31 is shrink fit to the main shell 11, only the annular protrusion 314 contacts the first inner wall surface portion 111 of the main shell 11. For this reason, the amount of deformation of the first inner wall surface portion 111 of the main shell 11 is in a small state. Furthermore, when the circumference of the upper shell 12 is welded, the small diameter end portion 315 also contacts the first inner wall surface portion 111 of the main shell 11 together with the annular projection 314.

At this time, a main load 319A caused by the contraction of the main shell 11 acts on the annular protrusion 314. Also, the load 319 B acts on the small diameter end 315. However, the load 319B is a smaller load than the main load 319A.

Here, the first inner wall surface portion 111 is inclined and deformed. Thereby, the annular protrusion 314 is deformed in an inclined manner. The main load 319A acts on the contact range s of the annular protrusion 314 within the axial range on the drive shaft 6 from the middle point (s / 2) position of the annular protrusion 314 to one end side U to s / 6. Therefore, if the position of the gravity center position 311G of the first circular base plate 311 is within this range, a large bending moment does not act on the first circular base plate 311 and the first spiral body 312. As a result, the deformation of the fixed scroll 31 is small.

If the contact range s is sufficiently small, the bending moment can be ignored. If the contact range s is 6% or less of the outermost diameter R1 of the annular projection 314, the bending moment becomes the load deflection level at the maximum load operation and can be sufficiently ignored.

According to the fifth embodiment, the influence of the bending moment can be sufficiently reduced, although the influence of the variation of the amount of contraction and deformation of the main shell 11 after welding remains, as compared with the first embodiment. Thereby, the effect according to the first embodiment can be obtained.

<Effect of Fifth Embodiment>
According to the fifth embodiment, the small diameter end 315 has a small diameter projection 315A that protrudes radially outward.

According to this configuration, the bending moment received by the small diameter end 315 having the small diameter projection 315A from the first inner wall surface portion 111 is smaller than the bending moment received by the annular projection 314 in contact with the first inner wall surface portion 111 or zero. is there. As a result, the influence of the deformation of the first circular base plate 311 and the first spiral body 312 can be ignored small enough.

In the fifth embodiment, the small diameter protrusion 315A is in contact with the first inner wall surface portion 111 of the main shell 11. Therefore, the small diameter protrusion 315A receives a bending moment smaller than the bending moment received by the annular protrusion 314 of the fixed scroll 31 in contact with the first inner wall surface portion 111. However, it is not limited to this. The small diameter projection 315A may not be in contact with the first inner wall surface portion 111 of the main shell 11.

<Others>
For example, in the above embodiment, the vertical scroll compressor has been described. However, the present invention can also be applied to a horizontal scroll compressor in which the drive shaft extends in the horizontal direction. At that time, also in the horizontal scroll compressor, the side on which the compression mechanism portion is provided can be defined as one end side and the side on which the drive mechanism portion is provided can be defined as the other end side with reference to the main frame. Moreover, it is not limited to the low pressure shell type scroll compressor. The present invention can also be applied to a high pressure shell type scroll compressor in which the pressure of the space in the main shell in which the drive mechanism is disposed is higher than the pressure of the refrigerant intake space.

The main shell is not limited to a cylindrical shape. The main shell may be, for example, a polygonal cylinder such as a hexagonal cylinder and a pentagonal cylinder. Further, in the above embodiment, the scroll body and the like can be designed as conventionally by the effect that the refrigerant intake space between the circular base plate of the fixed scroll in the main shell and the thrust bearing of the main frame can be expanded more than before. The diameters of the circular base plate and thrust plate of the oscillating scroll can be increased. As a result, the sliding area between the circular base plate of the oscillating scroll and the thrust plate is increased, and the thrust load can be reduced. However, it is not limited to this.

When the second scroll body and the second circular base plate of the rocking scroll are large, the weight is increased and the centrifugal force by the rocking motion of the rocking scroll is increased. Therefore, it is necessary to increase the volume and weight of the weight portion of the balance weight to offset the centrifugal force. On the other hand, in the present invention, there is no wall for bolting in the main frame, and the design freedom of the main frame is enhanced. For this reason, the accommodation space of the main-body part of a mainframe can be ensured large. As the accommodation space is increased, a balance weight having a large volume weight portion can be used. Therefore, the centrifugal force of the oscillating scroll is offset, and the radial load acting on the second scroll of the oscillating scroll can be reduced. Therefore, the reliability of the rocking scroll can be improved, and the sliding loss between the second scroll of the rocking scroll and the first scroll of the fixed scroll can be reduced.

In addition, the size of the oscillating scroll may be used as it is, and the shell, that is, the main shell or the upper shell may have an inner diameter smaller than that of the conventional one. As a result, a compact scroll compressor can be realized while maintaining the same displacement as in the prior art.

The first protrusion and the first positioning surface may adopt various shapes or manufacturing methods as long as they can position the fixed scroll with high accuracy. For example, the first protrusion only needs to be able to position the fixed scroll. For this reason, the first protrusion may be configured by at least two or more protrusions formed on the inner wall surface of the main shell. Further, the first protrusion may form the first protrusion by tapping from the outside of the main shell. In addition, a convex portion may be formed on the first positioning surface, a fixed scroll concave portion may be formed, and rotation of the fixed scroll with respect to the main shell may be suppressed by fitting the convex portion and the concave portion.

Further, the convex portion or concave portion formed on the thrust plate and the projecting wall portion protrudes in the direction of the projecting wall portion on the thrust plate to form a pair of projecting portions, and also forms a notch on the projecting wall. And a pair of projection may be arranged at a notch. Thus, the rotation of the thrust plate can be suppressed as in the first embodiment.

The thrust plate is not essential. The flat surface of the main frame may be configured to slide with the oscillating scroll.

A second convex portion or first concave portion engaged with the first convex portion or the first concave portion in the direction along the central axis of the drive shaft, and the first convex portion or the first concave portion in the main frame and fixed scroll in the inner wall surface of the main shell You may form 2 convex parts. Thereby, the phases of the first scroll of the fixed scroll and the second scroll of the oscillating scroll are matched. Therefore, the process of adjusting the phase by rotating the fixed scroll with respect to the oscillating scroll can be omitted.

Sixth Embodiment
<Refrigeration cycle apparatus 200>
FIG. 22 is a refrigerant circuit diagram showing a refrigeration cycle apparatus 200 to which the scroll compressor 100 according to Embodiment 6 of the present invention is applied.

As shown in FIG. 22, the refrigeration cycle apparatus 200 includes a scroll compressor 100, a condenser 201, an expansion valve 202 and an evaporator 203. The scroll compressor 100, the condenser 201, the expansion valve 202, and the evaporator 203 are connected by refrigerant pipes to form a refrigeration cycle circuit. Then, the refrigerant flowing out of the evaporator 203 is drawn into the scroll compressor 100 and becomes high temperature and high pressure. The high temperature and pressure refrigerant is condensed in the condenser 201 to become a liquid. The refrigerant that has become a liquid is decompressed and expanded by the expansion valve 202 and becomes a low-temperature low-pressure gas-liquid two phase, and the gas-liquid two-phase refrigerant is heat-exchanged in the evaporator 203.

The scroll compressor 100 according to the first to fifth embodiments can be applied to such a refrigeration cycle apparatus 200. In addition, as refrigeration cycle apparatus 200, an air conditioning apparatus, a freezing apparatus, a water heater, etc. are mentioned, for example.

<Effect of Sixth Embodiment>
The refrigeration cycle apparatus 200 includes the scroll compressor 100 described in the above first to fifth embodiments.

According to this configuration, in the refrigeration cycle apparatus 200 including the scroll compressor 100, the fixed scroll 31 can be disposed with high position accuracy in the shell 1, and the first spiral body 312 of the fixed scroll 31 and the second spiral of the oscillating scroll 32 The tooth tips of the body 322 are configured to be in an appropriate positional relationship.

Reference Signs List 1 shell, 2 main frame, 3 compression mechanism portion, 4 drive mechanism portion, 5 sub frame, 6 drive shaft, 7 bush, 8 power feed portion, 11 main shell, 12 upper shell, 13 lower shell, 14 suction pipe, 15 discharge pipe , 17 fixed base, 21 main body part, 22 main bearing part, 23 oil return pipe, 24 thrust plate, 31 fixed scroll, 32 rocking scroll, 33 oldham ring, 34 compression chamber, 35 muffler, 36 discharge valve, 41 stator, 42 Rotor 51 sub bearing portion 52 oil pump 61 main shaft portion 62 eccentric shaft portion 63 oil passage 64 first balancer 65 second balancer 71 slider 72 balance weight 81 cover 82 feeding terminal 83 Wiring, 91 discharge space, 92 suction space, 00 scroll compressor, 110 end portion, 111 first inner wall surface portion, 112 first projecting portion, 113 first positioning surface, 114 second projecting portion, 115 second positioning surface, 121 welding portion, 200 refrigeration cycle device, 201 condensation , 202 expansion valve, 203 evaporator, 211 accommodation space, 212 flat surface, 213 suction port, 214 Oldham accommodation portion, 215 first oldham groove, 216 projecting wall portion, 217 projection, 221 axial hole, 241 notch, 311 1st circular base plate, 311G barycentric position, 311X corner, 311a discharge port, 312 1st spiral body, 313 mounting end, 314 annular projection, 314A apex, 314X end, 314Y end, 315 small diameter end , 315A small diameter projection, 316 mounting projection, 317A sealing surface, 17B seal surface, 317 O seal surface, 318 concave portion, 321 second circular base plate, 322 second spiral body, 323 cylindrical portion, 324 second oldham groove, 331 ring portion, 332 first key portion, 333 second key portion , 351 discharge hole, 721 weight portion, 1131 recess, 1151 recess.

Claims

A frame slidably holding the oscillating scroll;
A fixed scroll forming a compression chamber with the oscillating scroll;
A shell for securing the fixed scroll separately from the frame;
Equipped with
The shell has a cylindrical main shell including a thick portion and a thin portion formed to be thin with a larger inner diameter than the thick portion.
The fixed scroll has a mounting end mounted on a boundary between the thick portion and the thin portion, and an annular protrusion having a larger diameter than the mounting end and contacting the thin portion. A scroll compressor having a small diameter end portion smaller in diameter than the annular projection on the opposite side of the placement end portion via the annular projection.
The scroll compressor according to claim 1, wherein the placement end and the annular protrusion are separately formed.
The scroll compressor according to claim 2, wherein the annular protrusion is formed in a curved shape in an axial direction of the main shell.
The scroll compressor according to claim 1, wherein the placement end and the annular protrusion are integrally formed.
The scroll compressor according to claim 4, wherein the annular protrusion is linearly formed in an axial direction of the main shell.
The mounting projection according to any one of claims 1 to 5, wherein the mounting end, the annular projection, and the small diameter end are provided on a mounting projection projecting radially outward from a circular base plate of the fixed scroll. Scroll compressor.
The scroll compressor according to any one of claims 1 to 6, wherein a center of gravity of the circular base plate of the fixed scroll in the axial direction of the main shell is within the range of the annular projection.
The position of the center of gravity of the circular base plate of the fixed scroll in the axial direction of the main shell is within the range of the annular projection and on the small diameter end side with respect to the middle of the annular projection in the axial direction of the main shell. The scroll compressor according to claim 7.
The shell has an end shell to which the thin-walled portion of the main shell is fixed to close an opening on the thin-walled side of the main shell.
The scroll compressor according to any one of claims 1 to 8, wherein the thin portion of the main shell and the end shell are joined, and the small diameter end portion of the fixed scroll and the thin portion are separated.
The shell has an end shell to which the thin-walled portion of the main shell is fixed to close an opening on the thin-walled side of the main shell.
The bending moment that the small diameter end of the fixed scroll receives from the thin portion when the thin portion of the main shell is fixed to the end shell is the annular projection of the fixed scroll making contact with the thin portion The scroll compressor according to any one of claims 1 to 8, which is smaller than a bending moment received.
The scroll compressor according to any one of claims 1 to 10, wherein the small diameter end portion has a small diameter projection that protrudes radially outward.
A refrigeration cycle apparatus comprising the scroll compressor according to any one of claims 1 to 11.