JP2022132899A - Compressor and welding pin - Google Patents

Abstract

To inhibit plastic deformation of a welding pin during welding to maintain large holding power of the welding pin after the welding in a compressor in which the welding pin is press-fitted in a support member supporting a bearing, and fixedly welded to a casing.SOLUTION: A scroll compressor includes: a housing and a lower bearing housing which support a bearing metal rotatably supporting a driving shaft; a casing which houses the housing and the lower bearing housing therein; and a welding pin. The welding pin is press-fitted in holes formed at the housing and the lower bearing housing and fixedly welded to the casing. On an outer peripheral surface 62a of a body 62 of the welding pin before press-fitting, in a view seen in a welding pin press-fitted direction, multiple protruding parts 64 are formed along a circumferential direction of the welding pin to form a shape where crest parts 66 and valley parts 68 are alternately arranged. A first curvature radius ρ1 of a top 66a of the crest part is larger than a second curvature radius ρ2 of a bottom part 68a of the valley part.SELECTED DRAWING: Figure 6

Description

The present disclosure relates to compressors and weld pins. Specifically, the present disclosure relates to a compressor in which welding pins are press-fitted into holes in the outer surface of a support member that supports bearings, and the welding pins and the casing are fixed by welding. The present disclosure also relates to a weld pin for use with this compressor.

Conventionally, as in Patent Document 1 (Japanese Patent Application Laid-Open No. 2017-25762), a welding pin provided with a plurality of protrusions on the outer peripheral surface is press-fitted into a hole formed on the outer surface of a support member that supports the bearing. A compressor is known in which a support member is fixed to a casing by welding with the casing.

In such a compressor, when the welding pin is press-fitted into the support member, the convex portion of the outer peripheral surface of the welding pin is plastically deformed. Further, when the welding pin and the casing are welded together, thermal expansion of the welding pin presses the convex portion of the outer peripheral surface of the welding pin against the supporting member, and the convex portion of the welding pin is further plastically deformed. Plastic deformation of the convex portion progresses during welding, and as a result of the loss of elasticity of the convex portion, there is a possibility that the holding force of the weld pin after welding may decrease. In addition, the holding force of the welding pin means the force for fixing the welding pin to the supporting member.

A compressor according to a first aspect includes a drive section, a compression mechanism, a drive shaft, a support member, a casing, and a welding pin. The drive shaft transmits the drive force of the drive unit to the compression mechanism. The support member supports bearings that rotatably support the drive shaft. A hole is formed in the outer surface of the support member. The casing houses the drive shaft and the support member inside. The weld pin has a cylindrical body portion with flat knurls formed on its outer peripheral surface. The welding pin is press-fitted into the hole of the support member and welded to the casing. On the outer peripheral surface of the main body of the weld pin before press-fitting, a plurality of protrusions are formed along the circumferential direction of the weld pin when viewed from the press-fit direction of the weld pin, and the peaks and valleys are alternately arranged. It's becoming The first radius of curvature, which is the radius of curvature at the top of the peak portion, is greater than the second radius of curvature, which is the radius of curvature at the bottom of the valley portion.

In the compressor of the first aspect, since the first radius of curvature is larger than the second radius of curvature, the contact surface between the main body and the support member is made larger than when the first radius of curvature is equal to or less than the second radius of curvature. be able to. Therefore, in the compressor of the first aspect, plastic deformation of the weld pin during welding can be suppressed, and a large holding force of the weld pin after welding can be maintained.

A compressor according to the second aspect is the compressor according to the first aspect, wherein the first radius of curvature of the weld pin before press-fitting is 10 times or more the second radius of curvature.

In the compressor of the second aspect, the contact surface between the main body and the support member can be made particularly large, plastic deformation of the weld pin during welding can be suppressed, and a large holding force of the weld pin after welding can be maintained. .

A compressor according to a third aspect is the compressor according to the first aspect or the second aspect, in which the first radius of curvature of the weld pin before press-fitting is equal to the radius from the center of the body portion to the top of the peak portion.

In the compressor of the third aspect, it is possible to secure a large contact surface between the main body and the support member, suppress plastic deformation of the weld pin during welding, and maintain a large holding force of the weld pin after welding.

A compressor according to a fourth aspect is the compressor according to any one of the first aspect to the third aspect, and the convex portion includes a first convex portion and a first convex portion arranged adjacent to the first convex portion. 2 protrusions. When imagining an imaginary circle having the same radius as the radius of the hole formed in the supporting member around the center of the body of the welding pin before press-fitting, as viewed from the press-fitting direction, the ratio of the first distance to the second distance is: , from 0.5 to 3.0. The first distance is two points of intersection of the virtual circle and the edge of the first protrusion: a first point of intersection proximal to the second protrusion and a second point distal to the second protrusion. is the distance between the intersection points. The second distance is the distance between the first intersection point and the third intersection point. The third point of intersection is the point of intersection between the edge of the second protrusion and the imaginary circle that is located near the first protrusion.

In the compressor of the fourth aspect, by increasing the ratio of the first distance to the second distance to 0.5 or more, it is possible to increase the contact surface between the main body and the support member, and the welding pin at the time of welding. plastic deformation can be suppressed, and a large holding force of the weld pin after welding can be maintained.

Further, in the compressor of the fourth aspect, since the ratio of the first distance to the second distance is 3.0 or less, the deformation margin of the convex portion during thermal expansion is secured, and the convex portion of the welding pin during welding is reduced. Plastic deformation can be suppressed.

A compressor according to a fifth aspect is the compressor according to any one of the first aspect to the fourth aspect, wherein the ratio of the first value to the second value is 0.3 or more and 1.6 or less. The first value is a value obtained by subtracting the radius of the hole formed in the support member from the distance from the center of the body portion to the apex of the peak portion in the weld pin before press fitting. The second value is the radius of the hole formed in the support member minus the distance from the center of the body portion to the deepest portion of the root portion of the weld pin before press fitting.

In the compressor of the fifth aspect, while ensuring a relatively large contact surface between the main body and the support member, a deformation margin for the projections during thermal expansion is secured to prevent plastic deformation of the projections of the welding pin during welding. can be suppressed, and a large holding force of the welding pin can be maintained even after welding.

A compressor according to a sixth aspect is the compressor according to any one of the first aspect to the fifth aspect, wherein, when viewed in the press-fitting direction, the convex portion of the weld pin before press-fitting is the top portion of the peak portion and the bottom portion of the valley portion. has a straight portion extending between The angle formed by the linear portions of two adjacent convex portions forming the valley portion is 60° or more and less than 95°.

In the compressor of the sixth aspect, while ensuring a relatively large contact surface between the main body and the support member, a deformation margin for the convex portion during thermal expansion is secured to prevent plastic deformation of the convex portion of the welding pin during welding. can be suppressed, and a large holding force of the welding pin can be maintained even after welding.

A compressor according to a seventh aspect is the compressor according to any one of the first aspect to the sixth aspect, wherein the distance from the center of the body portion to the apex of the peak portion of the weld pin before press-fitting is calculated from is 0.2 mm or more and 0.4 mm or less.

A compressor according to an eighth aspect is the compressor according to any one of the first aspect to the seventh aspect, wherein the support member has an arm extending from the bearing support portion that supports the bearing toward the casing, and the end of the arm A hole is formed in the outer surface of the part.

The weld pin of the ninth aspect is used for fixing the casing of the compressor and the support member that supports the bearing that rotatably supports the drive shaft that transmits the driving force of the drive part of the compressor to the compression mechanism of the compressor. be done. The weld pin has a cylindrical body. Flat knurling is formed on the outer peripheral surface of the main body. A welding pin is press-fitted into a hole formed in the outer surface of the support member and welded and fixed to the casing. On the outer peripheral surface of the main body of the weld pin before press-fitting, a plurality of protrusions are formed along the circumferential direction of the weld pin when viewed from the press-fit direction of the weld pin, and the peaks and valleys are alternately arranged. It's becoming The first radius of curvature, which is the radius of curvature at the top of the peak portion, is greater than the second radius of curvature, which is the radius of curvature at the bottom of the valley portion.

1 is a schematic vertical cross-sectional view of a scroll compressor according to an embodiment of the present disclosure; FIG. 2 is a schematic side view of the housing of the scroll compressor of FIG. 1; FIG. FIG. 2 is a diagram schematically showing a fixed state between a casing and a welding pin of the scroll compressor of FIG. 1; FIG. 2 is a view of a weld pin before press-fitting used in the scroll compressor of FIG. 1 as seen along a direction perpendicular to the press-fit direction of the weld pin; FIG. 2 is a view of a weld pin before press-fitting used in the scroll compressor of FIG. 1 as seen along the press-fit direction of the weld pin; FIG. 6 is an enlarged view of the vicinity of the outer peripheral surface of the main body of the welding pin when the welding pin of FIG. 5 is viewed along the press-fitting direction of the welding pin; FIG. 11 is an enlarged view of the vicinity of the outer peripheral surface of the main body of the welding pin when the welding pin of modification B is viewed along the press-fitting direction of the welding pin; It is a figure for demonstrating the shape of the knurling of the flat eye of JIS standard.

Embodiments of the compressor will be described with reference to the drawings.

Hereinafter, for convenience of explanation, expressions such as “upper” and “lower” may be used to describe the position and orientation. Unless otherwise specified, the positions and directions of expressions such as "top" and "bottom" follow the arrows in the drawings.

In addition, hereinafter, expressions such as “parallel”, “perpendicular”, “horizontal”, “perpendicular”, and “same” may be used, but these expressions are strictly meaning “parallel”, “perpendicular”. , “horizontal”, “vertical”, and “identical”. Expressions such as "parallel", "perpendicular", "horizontal", "perpendicular", "identical" shall mean substantially "parallel", "perpendicular", "horizontal", "perpendicular", "identical". Used in the sense of including.

(1) Overall Configuration An overview of a scroll compressor 100 according to an embodiment of the compressor of the present disclosure will be described with reference to FIG. FIG. 1 is a schematic longitudinal sectional view of a scroll compressor 100. FIG.

The scroll compressor 100 is used in refrigeration systems that use a vapor compression refrigeration cycle, such as air conditioners, water heaters, and floor heating systems. The scroll compressor 100 is mounted, for example, in a heat source unit of a refrigeration system and constitutes a part of a refrigerant circuit of the refrigeration system.

The scroll compressor 100 of the present disclosure is a hermetic compressor. The scroll compressor 100 sucks low-pressure (hereinafter, sometimes simply referred to as low-pressure) refrigerant in the refrigeration cycle, compresses the sucked refrigerant, and converts it to high-pressure (hereinafter, sometimes simply, high-pressure) refrigerant in the refrigeration cycle. to dispense. The refrigerant is, for example, HFC refrigerant R32. Note that R32 is merely an example of the type of refrigerant, and the scroll compressor 100 may be a device that compresses an HFC refrigerant other than R32 or an HFO refrigerant. Further, for example, the scroll compressor 100 may be a device that compresses and discharges a natural refrigerant such as carbon dioxide.

The scroll compressor 100 mainly has a casing 10, a compression mechanism 20, a housing 50, a motor 70, a drive shaft 80, a lower bearing housing 90, and weld pins 60, as shown in FIG.

(2) Detailed Configuration Details of the casing 10, the compression mechanism 20, the housing 50, the motor 70, the drive shaft 80, the lower bearing housing 90, and the weld pin 60 will be described.

(2-1) Casing The scroll compressor 100 has a vertically long cylindrical casing 10 (see FIG. 1).

The casing 10 mainly has a cylindrical member 12, an upper lid 14a and a lower lid 14b. The cylindrical member 12 is a cylindrical member extending along the central axis O and having top and bottom openings. The upper lid 14 a is provided above the cylindrical member 12 and closes the opening above the cylindrical member 12 . The lower lid 14 b is provided below the cylindrical member 12 and closes the opening below the cylindrical member 12 . The cylindrical member 12, the upper lid 14a and the lower lid 14b are fixed by welding so as to maintain airtightness.

The casing 10 accommodates therein various members constituting the scroll compressor 100 including the compression mechanism 20, the housing 50, the motor 70, the drive shaft 80 and the lower bearing housing 90 (see FIG. 1). A compression mechanism 20 is arranged in the upper part of the casing 10 . A housing 50 is arranged below the compression mechanism 20 . A motor 70 is arranged below the housing 50 . A lower bearing housing 90 is arranged below the motor 70 . An oil reservoir space 16 is formed in the bottom of the casing 10 . Refrigerant oil for lubricating various sliding parts of the scroll compressor 100 is stored in the oil reservoir space 16 .

Motor 70 is arranged in first space S<b>1 of scroll compressor 100 . In the present embodiment, the first space S1 is a space into which high-pressure refrigerant compressed by the compression mechanism 20 flows. In other words, the scroll compressor 100 of this embodiment is a so-called high pressure dome type scroll compressor. The first space S1 communicates with the oil reservoir space 16 below the casing 10 via a gap or the like formed between the cylindrical member 12 of the casing 10 and a stator 72 of the motor 70 (described later) (see FIG. 1). reference).

The scroll compressor 100 may not be a high-pressure dome-type scroll compressor, but may be a so-called low-pressure dome-type scroll compressor in which a motor is arranged in a space into which low-pressure refrigerant flows from a refrigerant circuit of a refrigeration system. There may be.

A suction pipe 18a, a discharge pipe 18b, and an injection pipe 18c are attached to the casing 10 so as to communicate the inside and the outside of the casing 10 (see FIG. 1).

The suction pipe 18a is provided through the upper lid 14a of the casing 10 as shown in FIG. One end of the suction pipe 18a (the end outside the casing 10) is connected to a pipe (not shown) of the refrigeration system, and the other end of the suction pipe 18a (the end inside the casing 10) is connected to the fixed scroll 30 of the compression mechanism 20. is connected to the suction port 36a. The suction pipe 18a communicates with a compression chamber Sc on the outer peripheral side of the compression mechanism 20, which will be described later, through a suction port 36a. The scroll compressor 100 sucks the low-pressure refrigerant in the refrigeration cycle of the refrigeration system through the suction pipe 18a.

The discharge pipe 18b is provided through the cylindrical member 12 at the central portion in the vertical direction of the cylindrical member 12, as shown in FIG. One end of the discharge pipe 18b (the end outside the casing 10) is connected to a pipe (not shown) of the refrigeration system, and the other end of the discharge pipe 18b (the end inside the casing 10) is connected to the housing 50 of the first space S1. and the motor 70 . The scroll compressor 100 discharges the high-pressure refrigerant compressed by the compression mechanism 20 through the discharge pipe 18b.

The injection pipe 18c is provided through the upper lid 14a of the casing 10 as shown in FIG. One end of the injection pipe 18c (the end outside the casing 10) is connected to a pipe (not shown) of the refrigeration system, and the other end of the injection pipe 18c (the end inside the casing 10) is connected to the fixed scroll 30 of the compression mechanism 20. connected to The injection pipe 18 c communicates with the compression chamber Sc in the middle of compression of the compression mechanism 20 via a passage (not shown) formed in the fixed scroll 30 . Intermediate-pressure refrigerant in the refrigerating cycle is supplied from the refrigerant circuit of the refrigerating device through the injection pipe 18c to the compression chamber Sc that is in communication with the injection pipe 18c. The intermediate pressure in the refrigerating cycle means intermediate pressure between the low pressure and the high pressure in the refrigerating cycle. Hereinafter, instead of describing the intermediate pressure in the refrigeration cycle, it may simply be referred to as the intermediate pressure.

(2-2) Compression Mechanism The compression mechanism 20 mainly has a fixed scroll 30 and a movable scroll 40 . The fixed scroll 30 and the movable scroll 40 are combined to form a compression chamber Sc. The compression mechanism 20 compresses the refrigerant in the compression chamber Sc and discharges the compressed refrigerant.

(2-2-1) Fixed Scroll The fixed scroll 30 is mounted on the housing 50 and fixed by fixing means (for example, bolts) not shown.

The fixed scroll 30 mainly has a fixed-side end plate 32, a fixed-side wrap 34, and a peripheral portion 36, as shown in FIG.

The fixed-side end plate 32 is a disk-shaped member. The fixed-side wrap 34 is a wall-shaped member that protrudes from the front surface 32 a (lower surface) of the fixed-side end plate 32 toward the movable scroll 40 . When the fixed scroll 30 is viewed from below, the fixed side wrap 34 is formed in a spiral shape (involute shape) from the vicinity of the center of the fixed side end plate 32 toward the outer peripheral side. The peripheral portion 36 is a thick cylindrical member that protrudes from the front surface 32 a of the fixed end plate 32 toward the movable scroll 40 . The peripheral edge portion 36 is arranged to surround the fixed side wrap 34 . A suction port 36 a is formed in the peripheral portion 36 . A downstream end of the suction pipe 18a is connected to the suction port 36a.

A fixed side wrap 34 of the fixed scroll 30 and a movable side wrap 44 of the orbiting scroll 40 (to be described later) are combined to form a compression chamber Sc. Specifically, the fixed scroll 30 and the orbiting scroll 40 are combined in such a manner that the front surface 32a of the fixed side panel 32 and the front surface 42a (upper surface) of the movable side panel 42, which will be described later, face each other. As a result, a compression chamber Sc surrounded by the fixed side end plate 32, the fixed side wrap 34, the movable side wrap 44, and the movable side end plate 42 of the movable scroll 40, which will be described later, is formed (see FIG. 1). When the movable scroll 40 orbits with respect to the fixed scroll 30, the low-pressure refrigerant that has flowed from the suction pipe 18a through the suction port 36a into the compression chamber Sc on the peripheral edge side is compressed as it moves to the compression chamber Sc on the central side. pressure rises.

A discharge port 33 for discharging the refrigerant compressed by the compression mechanism 20 is formed substantially at the center of the fixed-side end plate 32 so as to penetrate the fixed-side end plate 32 in the thickness direction (vertical direction) (see FIG. 1). ). The discharge port 33 communicates with the center side (innermost) compression chamber Sc of the compression mechanism 20 . A discharge valve 22 for opening and closing the discharge port 33 is attached above the fixed side end plate 32 . When the pressure in the innermost compression chamber Sc to which the discharge port 33 communicates becomes greater than the pressure in the discharge space Sa above the discharge valve 22 by a predetermined value or more, the discharge valve 22 opens and the innermost compression chamber Sc is opened. of refrigerant passes through the discharge port 33 and flows into the discharge space Sa above the fixed-side end plate 32 . The discharge space Sa communicates with a refrigerant passage (not shown) formed over the fixed scroll 30 and the housing 50 . The refrigerant passage is a passage that connects the discharge space Sa and the first space S1 below the housing 50 . The refrigerant that has been compressed by the compression mechanism 20 and flows into the discharge space Sa passes through the refrigerant passage and flows into the first space S1.

(2-2-2) Movable Scroll The movable scroll 40 mainly has a movable side end plate 42, a movable side wrap 44, and a boss portion 46, as shown in FIG.

The movable end plate 42 is a disk-shaped member. The movable wrap 44 is a wall-shaped member that protrudes from the front surface 42 a (upper surface) of the movable end plate 42 toward the fixed scroll 30 . When the orbiting scroll 40 is viewed from above, the orbiting side wrap 44 is formed in a spiral shape (involute shape) from the vicinity of the center of the orbiting side end plate 42 toward the outer peripheral side. The boss portion 46 is a cylindrical member that protrudes from the rear surface 42b (lower surface) of the movable end plate 42 toward the motor 70 side.

During operation of the scroll compressor 100 , the movable scroll 40 is pressed against the fixed scroll 30 by the pressure of a crank chamber 52 and a back pressure space 54 on the back surface 42 b side of the movable end plate 42 . By pressing the movable scroll 40 against the fixed scroll 30 , the gap between the tip of the fixed side wrap 34 and the movable side end plate 42 and the gap between the tip of the movable side wrap 44 and the fixed side end plate 32 . refrigerant leakage is suppressed.

The boss portion 46 is arranged in a later-described crank chamber 52 formed by the housing 50 . The boss portion 46 is formed in a cylindrical shape. The boss portion 46 extends downward from the back surface 42 b of the movable end plate 42 . The top of the cylindrical boss portion 46 is closed by the movable end plate 42 . A bearing metal 47 is arranged in the hollow portion of the boss portion 46 . An eccentric portion 84 of a drive shaft 80, which will be described later, is inserted into the hollow portion of the boss portion 46 (see FIG. 1). Since the drive shaft 80 is connected to the rotor 74 of the motor 70 as will be described later, when the motor 70 is driven and the rotor 74 rotates, the orbiting scroll 40 orbits.

The orbiting scroll 40 rotated by the motor 70 revolves around the fixed scroll 30 without rotating due to the action of the Oldham coupling 24 (see FIG. 1) arranged on the back surface 42b side of the orbiting scroll 40. .

When the movable scroll 40 revolves around the fixed scroll 30, the gas refrigerant in the compression chamber Sc of the compression mechanism 20 is compressed. Specifically, when the orbiting scroll 40 revolves, the gas refrigerant is sucked from the suction pipe 18a through the suction port 36a into the compression chamber Sc on the peripheral side, and then the compression chamber Sc moves toward the center of the compression mechanism 20 ( center side of the fixed side end plate 32). As the compression chamber Sc moves toward the center of the compression mechanism 20, the volume of the compression chamber Sc decreases and the pressure in the compression chamber Sc increases. As a result, the compression chambers Sc on the center side have a higher pressure than the compression chambers Sc on the peripheral edge side. The gas refrigerant compressed by the compression mechanism 20 to a high pressure is discharged into the discharge space Sa from the central compression chamber Sc through the discharge port 33 formed in the fixed side end plate 32 . The refrigerant discharged into the discharge space Sa passes through a refrigerant passage (not shown) formed in the fixed scroll 30 and the housing 50 and flows into the first space S<b>1 below the housing 50 .

(2-3) Housing The housing 50 will be described with further reference to FIGS. 2 and 3. FIG.

2 is a schematic side view of housing 50. FIG. FIG. 3 is a diagram schematically showing how casing 10 and welding pin 60 are fixed.

Housing 50 is a casting. The housing 50 mainly includes a first portion 120 and an upper bearing housing 110, as shown in FIG. The first part 120 is a cylindrical part. The upper bearing housing 110 is also cylindrically formed. The upper bearing housing 110 is arranged closer to the motor 70 than the first portion 120 in the axial direction of the drive shaft 80 . Upper bearing housing 110 is located closer to compression mechanism 20 than motor 70 .

Housing 50 is an example of a support member. Housing 50 supports bearing metal 112 provided in upper bearing housing 110 .

A fixed scroll 30 is fixed to the first portion 120 of the housing 50 . Specifically, the fixed scroll 30 is mounted on the housing 50 with the lower surface of the peripheral edge portion 36 of the fixed scroll 30 facing the upper surface of the housing 50, and is fixed to the housing 50 by a fixing member (for example, a bolt) not shown. ing. Housing 50 supports fixed scroll 30 fixed to first portion 120 .

Also, the housing 50 supports the movable scroll 40 arranged between the fixed scroll 30 and the first portion 120 of the housing 50 . Specifically, the housing 50 supports the orbiting scroll 40 from below via the Oldham coupling 24 arranged above the housing 50 .

The first part 120 of the housing 50 is a cylindrical member. The first part 120 of the housing 50 is fixed to the inner peripheral surface of the cylindrical member 12 of the casing 10 .

Specifically, the housing 50 is press-fitted into the cylindrical member 12 of the casing 10 , and the outer surface 122 of the first portion 120 extends partially along the entire circumference of the inner circumference of the cylindrical member 12 in the axial direction of the drive shaft 80 . close to the surface.

Moreover, the housing 50 is further fixed to the cylindrical member 12 of the casing 10 by welding. Fixing the housing 50 to the cylindrical member 12 by welding will be specifically described.

A hole 124 into which the welding pin 60 is press-fitted is formed in the outer surface 122 (outer surface) of the first portion 120 of the housing 50, as shown in FIG. The hole 124 has substantially the same shape as a cross section of the weld pin 60 cut in a direction perpendicular to the press-fit direction of the weld pin 60 (the direction in which the weld pin 60 is press-fit into the hole 124). However, the diameter of the welding pin 60 (including the convex portion 64 described later) before press-fitting is larger than the diameter of the hole 124 . Further, as will be described later, the outer peripheral surface 62a of the body portion 62 of the welding pin 60 is provided with unevenness, whereas the inner peripheral surface of the hole 124 is not provided with unevenness. In this embodiment, the shape of hole 124 is circular. The hole 124 does not penetrate the first portion 120 in the radial direction of the cylindrical member 12 of the casing 10 . In other words, the hole 124 is a recess that does not penetrate the housing 50 in the radial direction of the cylindrical member 12 .

Although the dimensions are not limited, in this embodiment the hole 124 has a diameter of 12 mm (with a radius R of 6 mm) and a depth A of 9 mm. Depth A of hole 124 refers to the depth of hole 124 from outer surface 122 of first portion 120 to bottom 125 of hole 124 . The bottom portion 125 of the hole 124 means the inner wall portion of the portion where the radius of the hole 124 is the radius R in the radial direction of the cylindrical member 12 . A total of eight holes 124 are formed in the outer surface 122 of the housing 50, although the number is not limited. Although the positions are not limited, the outer surface 122 of the housing 50 is formed with four holes 124 at intervals of 90° in the circumferential direction and two holes 124 each in the axial direction of the drive shaft 80 (vertical direction here). It is

A through hole 12a as shown in FIG. 3 is formed in the cylindrical member 12 of the casing 10 at a position corresponding to the welding pin 60 of the housing 50 press-fitted into the cylindrical member 12 (position corresponding to the hole 124 of the housing 50). It is The welding pin 60 press-fitted into the hole 124 and the cylindrical member 12 of the casing 10 are fixed by welding at the position of the through hole 12a. A portion indicated by reference numeral 69 in FIG. 3 indicates a welded portion between the welding pin 60 and the cylindrical member 12 . The welding pin 60 press-fitted into the hole 124 of the first portion 120 of the housing 50 is welded and fixed to the cylindrical member 12, so that the housing 50 is also fixed to the cylindrical member 12 of the casing 10 by welding.

The reason why the housing 50 and the casing 10 are not directly welded but the welding pins 60 and the casing 10 are welded is that the housing 50 is a cast product and it is generally difficult to weld the cast product. be.

The housing 50 is further explained.

The first part 120 of the housing 50 has, as shown in FIG. 1 , a first recess 56 that is recessed in the center and a second recess 58 that surrounds the first recess 56 . The first recessed portion 56 surrounds the side surface of the crank chamber 52 in which the boss portion 46 of the orbiting scroll 40 is arranged. The second recessed portion 58 forms an annular back pressure space 54 on the back surface 42 b side of the movable end plate 42 .

During operation of the scroll compressor 100 , refrigerating machine oil flows into the crank chamber 52 from the first space S<b>1 and the oil reservoir space 16 . Therefore, during steady operation of the scroll compressor 100 (when the operation of the scroll compressor 100 is stable), the pressure in the crank chamber 52 becomes the high pressure in the refrigeration cycle of the refrigeration system. As a result, during steady operation of the scroll compressor 100, the central portion of the back surface 42b of the movable end plate 42 facing the crank chamber 52 is pushed toward the fixed scroll 30 with high pressure.

When the orbiting scroll 40 rotates during operation of the scroll compressor 100, the back pressure space 54 is filled with pressure through a hole (not shown) formed in the orbiting end plate 42 for a predetermined period of time while the orbiting scroll 40 rotates once. It communicates with the compression chamber Sc during compression. Therefore, during steady operation of the scroll compressor 100, the pressure in the back pressure space 54 becomes intermediate pressure in the refrigeration cycle of the refrigeration system (pressure between high pressure and low pressure in the refrigeration cycle of the refrigeration system). As a result, during steady operation of the scroll compressor 100, the peripheral edge portion of the back surface 42b of the movable end plate 42 facing the back pressure space 54 is pushed toward the fixed scroll 30 with intermediate pressure.

As a result of the above configuration, during steady operation of the scroll compressor 100 , the movable scroll 40 is pressed against the fixed scroll 30 by the high pressure in the crank chamber 52 and the intermediate pressure in the back pressure space 54 . The crank chamber 52 and the back pressure space 54 are separated from each other by an annular wall portion 57 arranged at the boundary between the first concave portion 56 and the second concave portion 58 (see FIG. 1). A seal ring (not shown) is arranged at the upper end of the wall portion 57 facing the back surface 42 b of the movable end plate 42 so as to seal between the crank chamber 52 and the back pressure space 54 .

The upper bearing housing 110 is cylindrically formed. A bearing metal 112 that rotatably supports the drive shaft 80 is provided inside the cylindrical upper bearing housing 110 . The bearing metal 112 is an example of a bearing. During operation of the scroll compressor 100 , a moment may act on the drive shaft 80 to overturn the drive shaft 80 . A resilient groove 115 is formed in the connecting portion between the upper bearing housing 110 and the first portion 120 to allow the inclination of the upper bearing housing 110 when a moment acts on the drive shaft 80 .

(2-4) Motor The motor 70 is an example of a driving section. The motor 70 has an annular stator 72 fixed to the inner wall surface of the cylindrical member 12 of the casing 10, and a rotor 74 arranged inside the stator 72 (see FIG. 1).

The rotor 74 is rotatably accommodated inside the stator 72 with a small gap (not shown) from the stator 72 . Rotor 74 is connected to orbiting scroll 40 of compression mechanism 20 via drive shaft 80 . Specifically, the rotor 74 is connected to the boss portion 46 of the movable scroll 40 via a drive shaft 80 (see FIG. 1). The motor 70 rotates the movable scroll 40 by rotating the rotor 74 .

(2-5) Drive shaft The drive shaft 80 connects the rotor 74 of the motor 70 and the movable scroll 40 of the compression mechanism 20 . The drive shaft 80 extends vertically. The drive shaft 80 transmits the driving force of the motor 70 to the movable scroll 40 of the compression mechanism 20 .

The drive shaft 80 mainly has a main shaft 82 and an eccentric portion 84 (see FIG. 1).

The main shaft 82 extends vertically from the oil reservoir space 16 to the crank chamber 52 . The main shaft 82 is rotatably supported by the bearing metal 112 of the upper bearing housing 110 and the bearing metal 91 arranged in the lower bearing housing 90 which will be described later. Further, the main shaft 82 is inserted through the rotor 74 of the motor 70 between the upper bearing housing 110 and the lower bearing housing 90 of the housing 50 and connected to the rotor 74 . The central axis of main shaft 82 coincides with central axis O of cylindrical member 12 of casing 10 .

The eccentric portion 84 is arranged at the upper end of the main shaft 82 . The central axis of the eccentric portion 84 is eccentric with respect to the central axis of the main shaft 82 . The eccentric portion 84 is inserted into the boss portion 46 of the movable scroll 40 and rotatably supported by the bearing metal 47 arranged inside the boss portion 46 .

An oil passage 86 is formed in the drive shaft 80 . The oil passage 86 has a main path 86a and branch paths (not shown). The main path 86 a extends axially through the drive shaft 80 from the lower end to the upper end of the drive shaft 80 . The branch path extends from the main path in a direction crossing the axial direction of drive shaft 80 . The refrigerating machine oil in the oil reservoir space 16 is pumped up by a pump (not shown) provided at the lower end of the drive shaft 80, passes through an oil passage 86, and flows through the sliding of the drive shaft 80 and the bearing metals 47, 112, 91. section, sliding section of the compression mechanism 20, and the like.

(2-6) Lower Bearing Housing The lower bearing housing 90 is an example of a support member. The lower bearing housing 90 supports a bearing metal 91 (bearing) that rotatably supports the drive shaft 80 .

A lower bearing housing 90 (see FIG. 1) is located below the motor 70 .

The lower bearing housing 90 mainly has a bearing support 92 and a plurality of arms 94 . Lower bearing housing 90 is a casting.

The bearing support portion 92 is formed in a cylindrical shape. A bearing metal 91 that rotatably supports the drive shaft 80 is provided inside the cylindrical bearing support portion 92 . The bearing support portion 92 supports the bearing metal 91 .

Arm 94 extends from bearing support 92 toward casing 10 . For example, the arms 94 extend radially from the bearing support 92 to the cylindrical member 12 of the casing 10 . In a non-limiting manner, the lower bearing housing 90 has three arms 94 . Although the structure is not limited, the bearing support portion 92 is provided with three arms 94 that are approximately evenly spaced (separated by about 120 degrees) in the circumferential direction of the cylindrical member 12 of the casing 10 . . A hole 96 into which a welding pin 60 is press-fitted is formed in the outer surface 94a of the end of each arm 94 (the surface of the end of the arm 94 extending from the bearing support portion 92 facing the cylindrical member 12 of the casing 10). there is For example, two holes 96 are arranged side by side in the axial direction (vertical direction here) of the drive shaft 80 in the outer surface 94a of the end of each arm 94 . Note that the two holes 96 may not be arranged side by side in the axial direction of the drive shaft 80 , and may be displaced in the circumferential direction of the cylindrical member 12 of the casing 10 .

In the present embodiment, each arm 94 is provided with two holes 96 into which the welding pins 60 are press-fitted, but the present invention is not limited to this. For example, each arm 94 may have one hole 96 into which the welding pin 60 is press-fitted. Also, the number of holes 96 into which the welding pins 60 are press-fitted in each arm 94 may be three or more.

The shape and dimensions of the hole 96 formed in the arm 94 are similar to the shape and dimensions of the hole 124 formed in the first portion 120 of the housing 50 . Here, in order to avoid duplication of description, detailed description of the shape and dimensions of the hole 96 is omitted.

A through hole 12a is formed in the cylindrical member 12 of the casing 10 at a position corresponding to the weld pin 60 of the lower bearing housing 90 (a position corresponding to the hole 96 of the lower bearing housing 90), as shown in FIG. . 3, the welding pin 60 is welded and fixed to the cylindrical member 12 of the casing 10 at the position of the through hole 12a. As a result of the welding pins 60 press-fitted into the holes 96 of the lower bearing housing 90 being welded and fixed to the cylindrical member 12, the lower bearing housing 90 is fixed to the cylindrical member 12 of the casing 10 by welding.

The reason why the lower bearing housing 90 and the casing 10 are not directly welded to each other but the welding pin 60 press-fitted into the lower bearing housing 90 and the casing 10 is welded is that the lower bearing housing 90 is a cast product. This is because it is generally difficult to weld castings.

(2-7) Weld Pin The weld pin 60 will be described with further reference to FIGS. 4 to 6. FIG.

FIG. 4 shows the weld pin 60 before being press-fitted into the hole 124 of the first part 120 of the housing 50 or the hole 96 of the arm 94 of the lower bearing housing 90 along a direction perpendicular to the press-fit direction of the weld pin 60. It is a diagram. FIG. 5 is a view along the press-fit direction of the weld pin 60 before press-fitting into the hole 124 of the first part 120 of the housing 50 or the hole 96 of the arm 94 of the lower bearing housing 90 . FIG. 6 shows the welding pin 60 before being press-fitted into the hole 124 of the first part 120 of the housing 50 or into the hole 96 of the arm 94 of the lower bearing housing 90 when viewed along the press-in direction of the weld pin 60. 6 is an enlarged view of the vicinity of the outer peripheral surface 62a of the body portion 62 of the pin 60. FIG. The press-fitting direction of the weld pin 60 (hereinafter sometimes simply referred to as the press-fit direction) means that the weld pin 60 is inserted into the hole 124 of the first portion 120 of the housing 50 or the hole 96 of the arm 94 of the lower bearing housing 90. It means the direction in which it is press-fitted.

The weld pin 60 is press fit into the hole 124 in the first part 120 of the housing 50 supporting the bearing metal 112 or the hole 96 in the arm 94 of the lower bearing housing 90 supporting the bearing metal 91 . The shape of the weld pin 60 is described below. Unless otherwise specified, the following description of the shape of the weld pin 60 describes the shape of the weld pin 60 before it is press-fitted into the holes 124 and 96 .

As can be seen from FIGS. 4 and 5, the welding pin 60 is a substantially cylindrical member. The weld pin 60 has a substantially circular shape when viewed along the press-fitting direction, as shown in FIG. The press-fitting direction coincides with the axial direction of the cylindrical weld pin 60 .

As shown in FIG. 4, the welding pin 60 includes chamfered portions 61 arranged at both ends in the press-fitting direction, and a body portion 62 arranged between the two chamfered portions 61 in the press-fitting direction. Without limitation, the length L of the weld pin 60 is 8 mm.

A flat knurl is formed on the outer peripheral surface 62a of the cylindrical body portion 62 . Specifically, a plurality of grooves extending along the press-fitting direction are formed in the outer peripheral surface 62a of the body portion 62 . In other words, on the outer peripheral surface 62a of the body portion 62 of the welding pin 60 before press-fitting, a plurality of projections 64 extending along the press-fitting direction are formed along the circumferential direction of the welding pin 60 when viewed from the press-fitting direction of the welding pin 60. formed. As a result of this configuration, when the weld pin 60 is viewed along the press-fitting direction, the outer peripheral surface 62a of the main body portion 62 is formed with a peak portion 66 along the circumferential direction of the weld pin 60, as shown in FIG. It has a shape in which the valley portions 68 are arranged alternately.

The peak portion 66 includes an arcuate top portion 66a having a first curvature radius ρ1 when the welding pin 60 is viewed along the press-fitting direction (see FIG. 5). The apex 66a is a portion including the apex 66b of the ridge portion 66 that is arranged radially outermost with respect to the center O1 of the substantially cylindrical body portion 62 when viewed in the press-fitting direction of the welding pin 60 (see FIG. 5). . Specifically, here, the apex 66b is the central portion of each crest portion 66 in the circumferential direction of the weld pin 60 when the weld pin 60 is viewed along the press-fitting direction. Below, the distance from the center O1 of the main body portion 62 to the vertex 66b of the peak portion 66 (radius from the center O1 to the vertex 66b) is denoted by P1. Distance P1 can be represented by radius R+V1 (V1>0) (of holes 96 and 124).

The valley portion 68 includes an arc-shaped bottom portion 68a having a second curvature radius ρ2 when the welding pin 60 is viewed along the press-fitting direction (see FIG. 5). The bottom portion 68a is a portion that includes the deepest position (deepest portion 68b) of the valley portion 68 arranged radially inward most with respect to the center O1 of the substantially cylindrical body portion 62 as viewed in the press-fitting direction of the welding pin 60. There is (see Figure 5). Below, the distance from the center O1 of the main body portion 62 to the deepest portion 68b of the valley portion 68 is denoted by P2. Distance P2 can be represented by radius RV2 (V2>0) (of holes 96 and 124).

Note that the first radius of curvature ρ1 is greater than the second radius of curvature ρ2. Preferably, the first radius of curvature ρ1 is at least ten times greater than the second radius of curvature ρ2. More preferably, the first radius of curvature ρ1 is 15 times or more greater than the second radius of curvature ρ2. Also, preferably, the first radius of curvature ρ1 is equal to the radius (distance P1) from the center O1 of the cylindrical body portion 62 to the top portion 66a of the peak portion 66 (see FIG. 5). Although the shape is not limited, for example, the first radius of curvature ρ1 is about 6 mm (radius R) + 0.05 to 0.2 mm, which is the radius of the top portion 66a of the peak portion 66 from the center O1 of the main body portion 62. , the second radius of curvature ρ2 is about 0.05 to 0.2 mm.

In addition, in the welding pin 60, the radii of the holes 124 and 96 formed in the housing 50 as a support member and the lower bearing housing 90 are around the center O1 of the body portion 62 before press-fitting, as viewed in the press-fitting direction of the welding pin 60. When drawing a virtual circle IC (see the two-dot chain line in FIG. 5) having the same radius as R, it is preferable that the following numerical relationships are established.

For convenience of explanation, any one of the protrusions 64 formed on the outer peripheral surface 62a of the main body 62 is referred to as a first protrusion 64a, and the two protrusions adjacent to the first protrusion 64a are referred to as first protrusions 64a. One of the portions 64 is called a second convex portion 64b (see FIG. 6).

When viewed from the press-fitting direction, the virtual circle IC intersects the edge 65 of the first projection 64a at two points (see FIG. 6). Of the two points of intersection, the point of intersection on the proximal side of the second convex portion 64b is called a first point of intersection X1, and the point of intersection on the distal side of the second convex portion 64b is called a second point of intersection X2. The virtual circle IC also intersects the edge 65 of the second projection 64b at two points (see FIG. 6). Of the two intersections, the intersection located near the first protrusion 64a is called a third intersection X3.

Here, a first distance D1, which is the distance between the intersection point X1 and the intersection point X2 (the length of the arc between the intersection point X1 and the intersection point X2 on the virtual circle IC), and a distance between the intersection point X1 and the intersection point X3. Between the second distance D2, which is the distance (the length of the arc between the intersection point X1 and the intersection point X3 on the virtual circle IC), the ratio D1/D2 of the first distance D1 to the second distance D2 is preferably is 0.5 or more and 3.0 or less. More preferably, the ratio D1/D2 of the first distance D1 to the second distance D2 is 0.9 or more and 2.65 or less.

Furthermore, in the weld pin 60, the ratio V1/V2 of the first value V1 to the second value V2 is preferably 0.3 or more and 1.6 or less. More preferably, the ratio V1/V2 of the first value V1 to the second value V2 is 0.4 or more and 1.3 or less.

The first value V1 here is a value (P1-R ). The second value V2 is a value (R−P2) obtained by subtracting the distance P2 from the center O1 of the body portion 62 to the deepest portion 68b of the valley portion 68 in the welding pin 60 before press-fitting from the radius R of the holes 124, 96. be.

Further, from the distance P1 from the center O1 of the body portion 62 to the apex 66b of the peak portion 66 in the weld pin 60 before press-fitting, from the center O1 of the body portion 62 to the deepest portion 68b of the valley portion 68 in the weld pin 60 before press-fit. The value obtained by subtracting the distance P2 is preferably 0.2 mm or more and 0.4 mm or less. For example, but not limited to, the value obtained by subtracting the distance P2 from the distance P1 is 0.3 mm. However, the value obtained by subtracting the distance P2 from the distance P1 may be outside this numerical range.

Furthermore, when viewed from the press-fitting direction, the convex portion 64 of the welding pin 60 before press-fitting includes a straight portion 65a extending between the top portion 66a of the peak portion 66 and the bottom portion 68a of the valley portion 68, and the straight portion 65a and the top portion 66a. and a curved portion 65b that connects smoothly. The angle α (see FIG. 6) formed by the linear portions 65a of the two adjacent projections 64 forming the valley portion 68 is preferably 65° or more and less than 95°. Although not limiting, in this embodiment the angle α is 70°.

In addition, the following effects are obtained by using such a shape.

First, problems that occur in conventional weld pins will be described.

There is a JIS standard (JISB0951) for the shape of knurling. Conventionally, when flat knurling is provided on a welding pin, knurling in accordance with this standard is provided.

The shape of knurling in the JIS standard will be described with reference to FIG. For example, according to the JIS standard (JISB0951), when the module m (length t/π in FIG. 8) is 0.3, the length t (pitch) in FIG. The first radius of curvature r1 of the top and the second radius of curvature r2 of the bottom of the valley are both 0.09 mm, and h is 0.198 mm. In short, the knurling according to the JIS standard has the same first radius of curvature r1 at the top of the peak and the second radius of curvature r2 at the bottom of the valley. When the module m is 0.2, the length t (pitch) is 0.628 mm, and the first curvature radius r1 at the top of the peak and the second curvature radius r2 at the bottom of the valley are both 0.06 mm. and h is 0.132 mm. Further, when the module m is 0.5, the length t (pitch) is 1.571 mm, and the first curvature radius r1 at the top of the peak portion and the second curvature radius r2 at the bottom of the valley portion are both 0.16 mm. and h is 0.326 mm.

Also, the angle formed by the linear portions of two adjacent convex portions forming the valley portion is 90°.

In short, the knurling according to the JIS standard has the same first radius of curvature r1 at the top of the peak and the second radius of curvature r2 at the bottom of the valley. In addition, the first curvature radius ρ1 (radius R+V1 of holes 96 and 124) of the top portion 66a of the crest portion 66 of the welding pin 60 of the present disclosure is the number of the first curvature radius r1 of the crest portion of the knurling in the JIS standard. Ten times.

In the case of a weld pin provided with flat knurls, when it is press-fitted into the holes 124, 96, the crest portion of the weld pin partially undergoes plastic deformation. Furthermore, the weld pin expands due to heat input during welding of the casing 10 to the cylindrical member 12, and the crest portions of the weld pin are pressed against the inner surfaces of the holes 124 and 96 into which they are press-fitted. plastic deformation. Since the weld pin, which has thermally expanded during welding, contracts after welding, the holding force of the weld pin whose crest elasticity has decreased due to plastic deformation with respect to the first portion 120 of the housing 50 and the arm 94 of the lower bearing housing 90 is , is reduced compared to before welding. Here, the holding force of the weld pin on the first portion 120 of the housing 50 and the arm 94 of the lower bearing housing 90 is a force acting on the press-fitted weld pin in a direction opposite to the press-fit direction of the weld pin. It means the maximum force that prevents the welding pin from moving in the direction opposite to the press-fitting direction.

When the drive shaft 80 rotates, a moment acts on the drive shaft 80 , and also acts on the upper bearing housing 110 and the lower bearing housing 90 provided with the bearing metals 112 and 91 that support the drive shaft 80 . As a result, during operation of the scroll compressor 100 , the first portion 120 of the housing 50 and the lower bearing housing 90 may be subjected to repetitive forces that are at least partially pulled away from the casing 10 . If the holding force of the weld pin is too small, the weld pin will be displaced in the direction opposite to the press-fitting direction due to the influence of the moment, and the fixing force of the housing 50 and the lower bearing housing 90 to the casing 10 against the cylindrical member 12 will decrease. Malfunction may occur.

The disclosing person of the present application believes that when using a welding pin provided with flat knurling according to the JIS standard (hereinafter sometimes referred to as a JIS welding pin), the holding force of the welding pin after welding may become too small. found out. On the other hand, when using the weld pin 60 provided with flat knurls having a shape as in the above-described embodiment, the present disclosure person has found that the first part 120 of the housing 50 of the weld pin 60 after welding and the lower bearing It was found that the decrease in holding force of the housing 90 with respect to the arm 94 is suppressed.

Actually, the degree to which the decrease in the holding force is suppressed depends on the post-welding holding force of the welding pin 60 press-fitted into the hole 124 of the first portion 120 of the housing 50 and the holding force of the first portion 120 of the housing 50. A comparison was made between the post-welding retention force of a weld pin press-fitted into the hole 124 and having flat knurls formed on the outer surface in accordance with the JIS standard (module m=0.3).

As a premise for the description, F represents the average value of the holding force after the weld pin is pressed into the housing 50 (before welding to the casing 10). It should be noted that the average value F of the holding force after press-fitting the weld pin into the housing 50 (before welding to the casing 10) is approximately the same when using the weld pin 60 of the present disclosure and when using the JIS weld pin.

When the welding pin 60 is used, the holding force of the welding pin 60 after welding can be expressed as an average of 0.4 F although there are variations. On the other hand, when a JIS welding pin is used, the holding force of the welding pin after welding decreases to an average of about 0.1 F although there are variations. In short, according to this experimental result, by using the welding pin 60, it is possible to secure the holding force of the welding pin 60 after welding to about four times that in the case of using the JIS welding pin.

The reason why the use of the weld pin 60 can suppress a decrease in the holding force of the weld pin 60 after welding to the first portion 120 of the housing 50 and the arm 94 of the lower bearing housing 90 compared to the case of using a JIS weld pin is as follows. , is estimated as follows.

First, since the first curvature radius ρ1 is larger than the second curvature radius ρ2, compared to the case of using a JIS welding pin having the same first curvature radius r1 and second curvature radius r2, the peak portion 66 of the welding pin 60 and A large contact surface with the inner peripheral surfaces of the holes 124 and 96 to be press-fitted can be secured. As a result, since the surface pressure acting on each crest portion 66 of the weld pin 60 is reduced, plastic deformation of the crest portion 66 of the weld pin 60 is likely to be suppressed.

In order to increase the contact surface between the peak portion 66 of the weld pin 60 and the inner peripheral surfaces of the holes 124 and 96 into which the weld pin 60 is press-fitted, it is conceivable to make the valley portion 68 of the weld pin 60 as small as possible. However, in this case, although the surface pressure acting on the crest portion 66 of the welding pin 60 is reduced, when the crest portion 66 comes into contact with the inner peripheral surfaces of the holes 124 and 96 into which it is press-fitted and is deformed, the crest portion 66 may be deformed. However, the elastically deformable gap is small, so there is a possibility that the plastic deformation of the peak portion 66 progresses.

Therefore, for example, by setting the ratio D1/D2 of the first distance D1 to the second distance D2 within the above range, a space is secured in which the peak portion 66 of the welding pin 60 can be elastically deformed, and the welding pin after welding is 60 to the housing 50 and the lower bearing housing 90 can be further suppressed. In addition to or instead of this, for example, by setting the ratio V1/V2 of the first value V1 to the second value V2 within the above range, the peak portion 66 of the welding pin 60 can be elastically deformed. Space can be secured to further suppress a decrease in the holding force of the weld pin 60 with respect to the housing 50 and the lower bearing housing 90 after welding.

(3) Operation of Scroll Compressor The operation of the scroll compressor 100 will be described. Here, the operation of the scroll compressor 100 in a steady state (when the operation is started and the operation is stable) will be described.

When the motor 70 is driven, the rotor 74 rotates, and the drive shaft 80 connected with the rotor 74 also rotates. When the drive shaft 80 rotates, the Oldham's coupling 24 causes the orbiting scroll 40 to revolve around the fixed scroll 30 without rotating. The low-pressure refrigerant in the refrigerating cycle of the refrigeration system that has flowed in from the suction pipe 18a is sucked into the compression chamber Sc on the peripheral side of the compression mechanism 20 via the suction port 36a. As the orbiting scroll 40 revolves and the volume of the compression chamber Sc decreases, the pressure in the compression chamber Sc increases. Refrigerant at an intermediate pressure (a pressure between a low pressure and a high pressure) in the refrigerating cycle of the refrigeration system is appropriately injected from the injection pipe 18c into the compression chamber Sc during compression. As the refrigerant moves from the compression chamber Sc on the peripheral side (outside) to the compression chamber Sc on the center side (inner side), the pressure of the refrigerant rises and finally reaches a high pressure in the refrigeration cycle of the refrigeration system. Refrigerant compressed by the compression mechanism 20 is discharged from a discharge port 33 located near the center of the fixed side end plate 32, passes through a refrigerant path (not shown) formed in the fixed scroll 30 and the housing 50, and enters the first space S1. flow into High-pressure refrigerant in the refrigeration cycle of the first space S1 is discharged from the discharge pipe 18b.

(4) Features (4-1)
A scroll compressor 100 of the present embodiment includes a motor 70 as an example of a drive unit, a compression mechanism 20, a drive shaft 80, a housing 50 and a lower bearing housing 90, a casing 10, and welding pins 60. ing. Housing 50 and lower bearing housing 90 are examples of support members. The drive shaft 80 transmits the driving force of the motor 70 to the compression mechanism 20 . The housing 50 supports a bearing metal 112 as an example of a bearing that rotatably supports the drive shaft 80 . The lower bearing housing 90 supports a bearing metal 91 as an example of a bearing that rotatably supports the drive shaft 80 . A hole 124 is formed in the outer surface 122 of the first portion 120 of the housing 50 . A hole 96 is formed in the outer surface 94 a of the arm 94 of the lower bearing housing 90 . The casing 10 accommodates the drive shaft 80, the housing 50 and the lower bearing housing 90 inside. The welding pin 60 has a columnar main body portion 62 with flat knurling formed on an outer peripheral surface 62a. The weld pin 60 is press-fitted into the hole 124 of the housing 50 and the hole 96 of the lower bearing housing 90 and welded to the casing 10 . A plurality of projections 64 are formed along the circumferential direction of the welding pin 60 on the outer peripheral surface 62a of the main body portion 62 of the welding pin 60 before press-fitting, as seen from the press-fitting direction of the welding pin 60. A peak portion 66 and a valley portion are formed. 68 are arranged alternately. The first radius of curvature ρ1, which is the radius of curvature of the top portion 66a of the peak portion 66, is larger than the second radius of curvature ρ2, which is the radius of curvature of the bottom portion 68a of the valley portion 68.

In the scroll compressor 100 of the present embodiment, since the first curvature radius ρ1 is larger than the second curvature radius ρ2, the contact surface between the body portion 62 of the weld pin 60 and the support member (housing 50 and lower bearing housing 90) is can be taken large. Therefore, plastic deformation of the weld pin 60 during welding can be suppressed, and a relatively large holding force of the weld pin 60 after welding can be maintained.

(4-2)
In the scroll compressor 100, preferably, in the weld pin 60 before press fitting, the first curvature radius ρ1 is ten times or more the second curvature radius ρ2.

In such a scroll compressor 100, the contact surface between the main body portion 62 of the weld pin 60 and the support member (housing 50 and lower bearing housing 90) can be made particularly large, and plastic deformation of the weld pin 60 during welding can be minimized. can be suppressed, and a large holding force of the weld pin 60 after welding can be maintained.

(4-3)
In the scroll compressor 100, preferably, in the weld pin 60 before press fitting, the first curvature radius ρ1 is equal to the radius (distance P1) from the center O1 of the body portion 62 of the weld pin 60 to the top portion 66a of the peak portion 66. .

In such a scroll compressor 100, the contact surface between the body portion 62 of the weld pin 60 and the support member (housing 50 and lower bearing housing 90) can be made large, and the holding force of the weld pin 60 after welding can be increased. can be kept large.

(4-4)
In the scroll compressor 100, the convex portion 64 of the weld pin 60 includes a first convex portion 64a and a second convex portion 64b arranged adjacent to the first convex portion 64a. Note that the first convex portion 64 a is an arbitrary convex portion 64 . As viewed from the press-fitting direction, a hypothetical Assuming a circle IC, the ratio (D1/D2) of the first distance D1 to the second distance D2 is preferably 0.5 or more and 3.0 or less.

Note that the first distance D1 is defined by a first intersection point X1 on the proximal side of the second convex portion 64b and a second convex portion 64b, which are two intersection points between the virtual circle IC and the edge portion 65 of the first convex portion 64a. It is the distance between the second intersection point X2 on the distal side of the portion 64b. The second distance D2 is the distance between the first intersection point X1 and the third intersection point X3. The third intersection X3 is an intersection located near the first projection 64a among the intersections between the edge 65 of the second projection 64b and the virtual circle IC.

In the scroll compressor 100, by increasing the ratio D1/D2 of the first distance D1 to the second distance D2 to 0.5 or more, the body portion 62 of the weld pin 60 and the support member (housing 50 and lower bearing housing 90) It is possible to secure a large contact surface with the welding pin 60, suppress plastic deformation of the welding pin 60 during welding, and maintain a large holding force of the welding pin 60 after welding.

In order to increase the contact surface between the body portion 62 of the weld pin 60 and the supporting member (housing 50 or lower bearing housing 90), it is possible to increase the ratio D1/D2 of the first distance D1 to the second distance D2. preferable. However, if the ratio D1/D2 is too large, in other words, if the width of the valley portion 68 is too small, the deformation allowance of the convex portion 64 during thermal expansion (the space that can be extended when the convex portion 64 is deformed). is reduced, the elastic deformation is restricted, and the plastic deformation of the convex portion 64 may progress. On the other hand, here, since the ratio D1/D2 is 3.0 or less, the deformation margin of the convex portion 64 during thermal expansion is secured, and the plastic deformation of the convex portion 64 of the welding pin 60 during welding is suppressed. be able to.

(4-5)
In the scroll compressor 100, the ratio V1/V2 of the first value V1 to the second value V2 is preferably 0.3 or more and 1.6 or less. The first value V1 is the distance P1 from the center O1 of the body portion 62 of the weld pin 60 before press-fitting to the apex 66b of the peak portion 66 to the hole 124, which is formed in the support member (housing 50 and lower bearing housing 90). It is a value obtained by subtracting the radius R of 96. The second value V2 is a value obtained by subtracting the distance P2 from the center O1 of the body portion 62 to the deepest portion 68b of the valley portion 68 in the welding pin 60 before press-fitting from the radius R of the holes 124,96.

In such a scroll compressor 100, while ensuring a relatively large contact surface between the main body portion 62 of the welding pin 60 and the supporting member (housing 50 and lower bearing housing 90), the deformation allowance of the convex portion 64 during thermal expansion is reduced. is ensured to suppress plastic deformation of the convex portion 64 of the welding pin 60 during welding, and a large holding force of the welding pin 60 can be maintained even after welding.

(4-6)
In the scroll compressor 100, the convex portion 64 of the welding pin 60 before press-fitting has a straight portion 65a extending between the top portion 66a of the peak portion 66 and the bottom portion 68a of the valley portion 68 when viewed from the press-fitting direction. The angle α formed by the linear portions 65a of the two adjacent projections 64 forming the valley portion 68 is preferably 60° or more and less than 95°.

In such a scroll compressor 100, while ensuring a relatively large contact surface between the main body portion 62 of the welding pin 60 and the supporting member (housing 50 and lower bearing housing 90), the deformation allowance of the convex portion 64 during thermal expansion is reduced. is ensured to suppress plastic deformation of the convex portion 64 of the welding pin 60 during welding, and a large holding force of the welding pin 60 can be maintained even after welding.

(4-7)
In the scroll compressor 100, the distance P1 from the center O1 of the body portion 62 to the apex 66b of the peak portion 66 in the weld pin 60 before press-fitting is the distance from the center O1 of the body portion 62 to the valley portion 68 in the weld pin 60 before press-fit. The value obtained by subtracting the distance P2 to the deepest portion 68b is preferably 0.2 mm or more and 0.4 mm or less.

(4-8)
In the scroll compressor 100 of the present embodiment, a lower bearing housing 90 has an arm 94 extending from a bearing support portion 92 that supports a bearing metal 91 toward the casing 10 . is formed.

(4-9)
The welding pin 60 of the present embodiment is a bearing that rotatably supports the casing 10 of the scroll compressor 100 and the drive shaft 80 that transmits the driving force of the motor 70 of the scroll compressor 100 to the compression mechanism 20 of the scroll compressor 100. It is used for fixing the housing 50 and the lower bearing housing 90 that support the metals 112 and 91 . The weld pin 60 has a cylindrical body portion 62 . The main body portion 62 is formed with flat knurling on the outer peripheral surface 62a. The weld pin 60 is press-fitted into holes 124 and 96 formed in the outer surfaces of the housing 50 and the lower bearing housing 90 and welded and fixed to the casing 10 . A plurality of projections 64 are formed along the circumferential direction of the welding pin 60 on the outer peripheral surface 62a of the main body portion 62 of the welding pin 60 before press-fitting, as seen from the press-fitting direction of the welding pin 60. A peak portion 66 and a valley portion are formed. 68 are arranged alternately. The first radius of curvature ρ1, which is the radius of curvature of the top portion 66a of the peak portion 66, is larger than the second radius of curvature ρ2, which is the radius of curvature of the bottom portion 68a of the valley portion 68.

(5) Modifications Modifications of the above embodiment are shown below. It should be noted that the following modified examples may be appropriately combined within a mutually consistent range.

(5-1) Modification A
Although the scroll compressor 100 has been described as an example of the compressor in the above embodiment, the type of compressor is not limited to the scroll compressor. In the configuration of the present disclosure in which a low-rigidity region is provided in a support member that supports a bearing that rotatably supports a drive shaft, a hole for press-fitting a welding pin is provided in the support member, and the welding pin and the casing are fixed by welding. It is widely applicable to machines. For example, the compressor of the present disclosure may be a rotary compressor.

(5-2) Modification B
The shape of the weld pin 60 described with reference to FIG. 6 in the above embodiment is merely an example, and other shapes such as those shown in FIG. 7 may be used. FIG. 7 is an enlarged view of the vicinity of the outer peripheral surface 62a of the body portion 62 of the weld pin 60 when the weld pin 60 of Modification B is viewed along the press-fitting direction of the weld pin 60. FIG. In addition, in description of the welding pin 60 of the modification B, the same code|symbol is used for the structure similar to the welding pin 60 of the said embodiment.

In the weld pin 60 of modification B, the first curvature radius ρ1 (=distance P1) is approximately 70 times the second curvature radius ρ2. In the weld pin 60 of modification B, the value of V1/V2 is 0.75. The value obtained by subtracting the distance P2 from the distance P1 is 0.35 mm. In the welding pin 60 of Modification B, the convex portion 64 of the welding pin 60 before press-fitting has a straight portion 65a extending between the top portion 66a of the peak portion 66 and the bottom portion 68a of the valley portion 68 when viewed from the press-fitting direction. , the angle α formed by the linear portions 65a of two adjacent convex portions 64 forming the valley portion 68 is 90°.

(5-3) Modification C
In the above embodiment, the first portion 120 of the housing 50 is provided with holes 124 at four locations in the circumferential direction of the cylindrical member 12 of the casing 10 and at two locations along the axial direction of the drive shaft 80 .

However, the first portion 120 of the housing 50 may be provided with one hole 124 at each of four locations in the circumferential direction of the cylindrical member 12 of the casing 10 .

Also, the first portion 120 of the housing 50 may be provided with three or more holes 124 at four locations in the circumferential direction of the cylindrical member 12 of the casing 10 .

(5-4) Modification D
In the above-described embodiment, the first portion 120 of the housing 50 is provided with two holes 124 aligned in the axial direction of the drive shaft 80 at four positions in the circumferential direction of the cylindrical member 12 of the casing 10 . .

However, the invention is not limited to this, and the hole 124 arranged below the first portion 120 of the housing 50 and the hole 124 arranged above the first portion 120 of the housing 50 are the cylinders of the casing 10. They may be arranged at different positions in the circumferential direction of the member 12 .

(5-5) Modification E
In the above embodiment, the housing 50 is fixed by press fitting and welding. However, the housing 50 is not limited to this, and the housing 50 may be fixed to the casing 10 only by welding (only by welding the welding pin 60 press-fitted into the hole 124 of the first part 120 and the casing 10). .

(5-6) Modification F
In the above embodiment, a vertical scroll compressor in which the axial direction of the drive shaft 80 is vertical is described as an example, but the compressor is a horizontal compressor in which the axial direction of the drive shaft 80 is horizontal. may be

(5-7) Modification G
In the above embodiment, the housing 50 and the lower bearing housing 90 respectively support the bearing metal 112 and the bearing metal 91 as examples of bearings, but are not limited to this. The housing 50 and lower bearing housing 90 may also support rolling bearings such as ball bearings in place of the bearing metals 112,91.

(5-8) Modification H
In the above embodiment, the first radius of curvature ρ1 is greater than the second radius of curvature ρ2 in all of the welding pins 60. However, it is not limited to this.

For example, a weld pin having a first radius of curvature ρ1 greater than the second radius of curvature ρ2 may be used only for a weld pin to which a particularly large force acts during operation of the scroll compressor 100 .

<Appendix>
Although embodiments of the present disclosure have been described above, it will be appreciated that various changes in form and detail may be made without departing from the spirit and scope of the present disclosure as set forth in the appended claims. .

INDUSTRIAL APPLICABILITY The present disclosure is widely applicable and useful to a compressor in which a welding pin is press-fitted into a hole on the outer surface of a support member that supports a bearing, and the welding pin and the casing are fixed by welding, and the welding pin used in this compressor. be.

10 casing 20 compression mechanism 50 housing (support member)
60 welding pin 62 body portion 62a outer peripheral surface 64 convex portion 64a first convex portion (convex portion)
64b Second protrusion (protrusion)
65 edge portion 65a straight portion 66 peak portion 66a top portion 66b peak 68 valley portion 68a bottom portion 68b deepest portion 70 motor (driving portion)
80 drive shaft 90 lower bearing housing (support member)
91 bearing metal (bearing)
92 bearing support 94a outer surface 96 hole 100 scroll compressor (compressor)
112 bearing metal (bearing)
122 Outer surface 124 Hole D1 First distance D2 Second distance IC Virtual circle O1 Main body center P1 Distance from the center of the main body to the top of the ridge, radius P2 from the center of the main body to the top of the ridge Radius R from the center to the deepest part of the valley portion Radius of hole V1 First value V2 Second value X1 First intersection X2 Second intersection X3 Third intersection α Angle ρ1 First radius of curvature ρ2 Second radius of curvature

JP 2017-25762 A

Claims (9)

a drive unit (70);
a compression mechanism (20);
a drive shaft (80) for transmitting the drive force of the drive unit to the compression mechanism;
support members (50, 90) having holes (124, 96) formed in outer surfaces (122, 94a) for supporting bearings (112, 91) that rotatably support the drive shaft;
a casing (10) housing the drive shaft and the support member therein;
A welding pin (60) having a cylindrical main body (62) with flat knurling formed on an outer peripheral surface (62a), press-fitted into the hole of the support member, and welded and fixed to the casing. When,
with
A plurality of projections (64) are formed along the circumferential direction of the welding pin on the outer peripheral surface of the main body portion of the welding pin before press-fitting, as viewed in the press-fitting direction of the welding pin. ) and valley portions (68) are alternately arranged, and the first radius of curvature (ρ1), which is the radius of curvature of the top portion (66a) of the peak portion, is the curvature radius of the bottom portion (68a) of the valley portion. greater than the second radius of curvature (ρ2), which is the radius
Compressor (100). In the weld pin before press-fitting, the first curvature radius is 10 times or more the second curvature radius,
A compressor according to claim 1 . In the weld pin before press-fitting, the first radius of curvature is equal to the radius (P1) from the center (O1) of the body portion to the top of the peak portion.
A compressor according to claim 1 or 2. The convex portion includes a first convex portion (64a) and a second convex portion (64b) arranged adjacent to the first convex portion,
When imagining an imaginary circle (IC) having the same radius as the radius (R) of the hole formed in the support member around the center (O1) of the main body portion before press-fitting, when viewed from the press-fitting direction,
Two points of intersection between the virtual circle and the edge (65) of the first protrusion, a first intersection point (X1) on the proximal side of the second protrusion and a far point on the second protrusion. The first distance (D1) is the distance between the second intersection point (X2) on the position side,
between the first intersection and a third intersection (X3) of intersections between the edge (65) of the second projection and the imaginary circle, which is located near the first projection; Assuming that the distance is the second distance (D2),
The ratio (D1/D2) of the first distance to the second distance is 0.5 or more and 3.0 or less.
A compressor according to any one of claims 1 to 3. A value obtained by subtracting the radius (R) of the hole formed in the support member from the distance (P1) from the center of the body portion to the apex (66b) of the peak portion in the weld pin before press-fitting is defined as a first Let the value (V1) be
A second value ( V2), then
The ratio (V1/V2) of the first value to the second value is 0.3 or more and 1.6 or less.
A compressor according to any one of claims 1 to 4. As viewed in the press-fitting direction, the convex portion of the welding pin before press-fitting has a straight portion (65a) extending between the top portion of the peak portion and the bottom portion of the valley portion, forming the valley portion. The angle (α) formed by the linear portions of the two adjacent convex portions is 60° or more and less than 95°.
A compressor according to any one of claims 1 to 5. From the distance (P1) from the center of the body portion to the peak (66b) of the peak portion (66b) of the weld pin before press-fitting, the distance (P1) from the center of the body portion to the deepest portion (68b) of the valley portion (68b) of the weld pin before press-fit ) is 0.2 mm or more and 0.4 mm or less,
A compressor according to any one of claims 1 to 6. The support member (90) has an arm (94) extending toward the casing from a bearing support (92) that supports the bearing (91), and the hole is formed on the outer surface (94a) of the end of the arm. (96) is formed,
A compressor according to any one of claims 1 to 7. A casing (10) of a compressor (100) and a bearing ( 112, 91) and a support member (50, 90) for fixing,
A columnar main body (62) having flat knurls formed on the outer peripheral surface (62a),
The welding pin is press-fitted into a hole (124, 96) formed in the outer surface (122, 94a) of the support member and welded to the casing,
A plurality of projections (64) are formed along the circumferential direction of the welding pin on the outer peripheral surface of the main body portion of the welding pin before press-fitting, as viewed in the press-fitting direction of the welding pin. ) and valley portions (68) are alternately arranged, and the first radius of curvature (ρ1), which is the radius of curvature of the top portion (66a) of the peak portion, is the curvature radius of the bottom portion (68a) of the valley portion. greater than the second radius of curvature (ρ2), which is the radius
Weld pin (60).

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