JP2008163844A - Scroll type fluid machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase compression efficiency by narrowing a gap between lap parts facing each other and increase productivity by shortening process time. <P>SOLUTION: A plurality of nearest parts 8 are provided on an outer circumference surface 3B of the lap part 3 of a fixed scroll 1 with keeping intervals in a scroll direction, and adjoining nearest parts 8 are connected with using a flat surface 8A. A plurality of nearest parts 14 are provided on an outer circumference surface 13B of the lap part 13 of a turning scroll 11 with keeping intervals in the scroll direction, and adjoining nearest parts 14 are connected with using a flat surface 14A. Consequently, outer circumference surfaces 3B, 13B of the lap parts 3, 13 can be formed in polygon shapes, an interval between the lap parts 3, 13 can be reduced and the shape can be simplified to shorten process time. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a scroll fluid machine suitable for use in, for example, an air compressor, a vacuum pump, or the like.

  In general, a scroll fluid machine includes a fixed scroll and a turning scroll provided to face the fixed scroll. In addition, the fixed scroll and the orbiting scroll include a disk-shaped end plate and a wrap that is erected in an axial direction on the end plate so as to be spirally wound from the inner diameter side to the outer diameter side of the end plate And each part. Thereby, the fixed scroll and the orbiting scroll define a plurality of compression chambers by overlapping each other's lap portions.

  The scroll type fluid machine sucks gas from the suction port provided on the outer diameter side of the fixed scroll by rotating the rotary scroll with a fixed turning radius with respect to the fixed scroll by the drive shaft, and sequentially in each compression chamber. The compressed fluid can be discharged outwardly from a discharge port provided on the inner diameter side of the fixed scroll.

  Also, in the scroll type fluid machine, by forming a plurality of protrusions on the peripheral surface of each lap portion, the gap between each lap portion is reduced to improve the sealing performance of the compression chamber and improve the compression efficiency. (For example, refer to Patent Documents 1 and 2). At this time, the plurality of protrusions are provided on the peripheral surface of the wrap portion with a space in the winding direction (spiral direction), and are protruded in the radial direction from the peripheral surface of the wrap portion as compared with the periphery.

JP 2004-138056 A JP 2004-293487 A

  By the way, the above-described scroll type fluid machine according to the prior art forms a plurality of protrusions extending in the axial direction on the peripheral surface of the lap portion, thereby reducing the compressed fluid leaking from between the facing lap portions, Improves airtightness.

  However, in the prior art, a concave portion that is recessed in the radial direction is formed between adjacent protrusions. At this time, although the projection contacts the lap portion of the other scroll, the concave portion does not contact the lap portion of the other scroll. For this reason, the air accumulated in the concave portion is not compressed and leaks toward the low pressure side after the peripheral surface of the counterpart lap portion passes, resulting in a problem that the compression efficiency is poor.

  Further, since the protrusion is provided on the peripheral surface of the lap portion formed of a curved surface, for example, a processing tool such as an end mill needs to be reciprocated in the radial direction in accordance with the protrusion, and there is a tendency that a processing error tends to occur. In addition, since the machining process becomes complicated, there are problems that the machining time is long and the productivity is low.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to reduce the interval between the lap portions facing each other to increase the compression efficiency and reduce the processing time to increase the productivity. It is an object of the present invention to provide a scroll fluid machine that can be enhanced.

  The scroll type fluid machine according to the present invention is provided with one scroll in which a wrap portion wound in a spiral shape from the inner diameter side to the outer diameter side is provided on the end plate, and the one scroll is opposed to the one scroll. The other lap portion, which is spirally wound from the inner diameter side to the outer diameter side so as to overlap the lap portion of the one scroll on the end plate and define a plurality of compression chambers, is erected in the axial direction. With scroll.

  In order to solve the above-mentioned problem, the feature of the configuration adopted by the invention according to claim 1 is that at least the outer peripheral surface of the wrap portion of the one scroll is in contact with the inner peripheral surface of the wrap portion of the other scroll. Alternatively, a plurality of closest approaching portions may be provided at intervals in the winding direction, and the adjacent closest approaching portions may be connected using a flat surface or a convex curved surface. It is in being separated with respect to the other scroll rather than an approach part.

  According to a second aspect of the present invention, the inner peripheral surface of the lap portion of the other scroll is in contact with or closest to the closest portion provided on the outer peripheral surface of the wrap portion of the one scroll. Alternatively, a plurality of convex curved closest approach surfaces are provided at intervals in the winding direction.

  In the invention of claim 3, at least one of the outer peripheral surface of the wrap portion of the one scroll and the inner peripheral surface of the wrap portion of the other scroll is made of a material softer than the closest portion. Thus, a soft film formed in a film shape is provided.

  According to a fourth aspect of the present invention, each closest approach portion is formed such that the interval dimension in the winding direction is narrow on the inner diameter side and wider on the outer diameter side.

  According to a fifth aspect of the present invention, each closest approach portion is formed with an equal angular interval from the inner diameter side to the outer diameter side of the lap portion.

  According to a sixth aspect of the present invention, each closest approach portion is formed only in a part of the lap portion standing on the end plate in the axial direction away from the end plate.

  According to a seventh aspect of the present invention, each closest approach portion is formed only on the inner diameter side in the winding direction of the wrap portion, and an involute curved surface portion according to an involute curve is provided on the outer diameter side of the wrap portion. Yes.

  According to the first aspect of the present invention, since the adjacent closest portions are connected using a flat surface or a convex curved surface, a recess may be formed between adjacent protrusions as in the prior art. Absent. For this reason, the space | interval of the lap | wrap part which mutually faces can be narrowed, the fluid which retains between wrap parts can be reduced, and compression efficiency can be improved.

  Moreover, since it was set as the structure which connects between the nearest approach parts using a flat surface or a convex curved surface, the cross section of the outer peripheral surface of the lap | wrap part in which the nearest approach part was provided can be formed in polygonal shape. For this reason, compared with the case where protrusion is provided in the peripheral surface of the wrap part which consists of a curved surface like a prior art, the shape of a wrap part can be simplified. As a result, for example, even when the lap portion is cut using a tool such as an end mill, it is not necessary to reciprocate the end mill in the radial direction, and the number of tool direction changes can be reduced. For this reason, since it is difficult to be influenced by backlash of the processing machine due to reciprocation, it is possible to reduce a processing error and process a highly accurate lap portion with little variation. In addition, compared to the case where protrusions are provided as in the prior art, the moving distance of the machining tool is shortened and the number of changes in the machining direction can be reduced, so the machining time of the lapping part can be shortened. , Productivity can be improved. Furthermore, a machining program can be easily set up just by giving the vertex coordinates of the polygonal shape, and the vertex coordinates can also be easily changed. For example, the shape of the lap portion can be easily changed according to the machine specifications and the like. it can.

  Moreover, since the closest approach part can be easily crushed or worn when it comes into contact with the peripheral surface of the facing lap part, it can be adapted to the peripheral surface of the lap part without contact many times. . As a result, power loss can be reduced, damage, noise, galling and the like can be prevented, and durability and reliability can be improved.

  Furthermore, when the angle between the adjacent closest parts of the lap part is increased, the galling resistance is improved, but the compression performance is lowered. On the other hand, if the angle between the adjacent closest portions of the wrap portion is reduced, the galling resistance is reduced, but the compression performance is improved. For this reason, a machine having the required characteristics can be manufactured by optimizing such a conflicting balance.

  According to the second aspect of the present invention, the inner peripheral surface of the wrap portion of the other scroll is flat or concavely curved in contact with or closest to the closest portion provided on the outer peripheral surface of the wrap portion of one scroll. Alternatively, since the plurality of convex curved closest approach surfaces are provided at intervals in the winding direction, the cross section of the inner peripheral surface of the wrap portion of the other scroll can be formed in a polygonal shape. For this reason, since the shape of a lap | wrap part can be simplified, the processing time of a lap | wrap part can further be shortened and productivity can be improved.

  According to the invention of claim 3, since the soft coating is provided on at least one of the inner peripheral surface and the outer peripheral surface of the lap portions facing each other, the soft coating is formed between each closest approach portion and the counterpart. It can be interposed between the lap parts. For this reason, for example, when the closest approach part approaches the counterpart lap part too much due to machine dimensional error, assembly error, etc., the soft member contacts the closest approach part or the counterpart lap part. In this case, since the soft coating can be easily deformed and adapted by contact with the closest part or the other party's lap part, galling, damage, etc. occur between them, and power loss, noise, etc. increase. Can be prevented.

  In addition, since the soft film is deformed only at the portion sandwiched between the closest portion and the wrap portion, the size of the gap formed between the wrap portions of each scroll can be reduced at the closed position of the compression chamber. it can. For this reason, the sealing property and compression efficiency of a compression chamber can be improved. Furthermore, even when the movement range of the closest part varies due to, for example, a dimensional error or an assembly error of the machine, the variation in the movement range of the closest part can be absorbed by the soft coating. For this reason, since processing, assembly, etc. of a scroll can be performed with minimum precision, a scroll type fluid machine can be manufactured efficiently.

  According to the fourth aspect of the present invention, each closest approach portion is formed such that the interval dimension P in the winding direction is narrow on the inner diameter side and wider on the outer diameter side, so that the radius of curvature of the wrap portion is on the inner diameter side. When it becomes smaller, a plurality of closest portions can be arranged at narrow intervals along this radius of curvature. For this reason, the clearance gap between the lap | wrap parts which face in a radial direction can be made small, the sealing performance of a compression chamber can be improved, and compression performance can be improved.

  According to the fifth aspect of the present invention, each closest approach portion is formed with a substantially equal angular interval from the inner diameter side to the outer diameter side of the wrap portion. It can be narrow on the inner diameter side and wider on the outer diameter side. In this case, the radius of curvature of the wrap portion becomes smaller on the inner diameter side, but a plurality of closest portions can be arranged at narrow intervals along the radius of curvature, so that a gap between the wrap portions facing in the radial direction is formed. The sealing property of the compression chamber can be increased by reducing the size, and the compression performance can be improved.

  According to the sixth aspect of the present invention, each closest approach portion is formed only in a part of the lap portion in the axial direction away from the end plate, so that, for example, when one scroll rotates, one scroll The closest approach portion can be brought closest to or in contact with the lap portion of the other scroll at the closed position of each compression chamber, and the sealability of each compression chamber can be enhanced by the closest approach portion.

  In addition, since the closest part is formed only in a part of the lap part in the axial direction away from the end plate, the axial length of the closest part can be shortened, and the noise generated by the closest part is reduced. can do. Moreover, since the closest approach part can be made small with respect to the axial direction of the wrap part, the average gap between the wrap part of the fixed scroll and the wrap part of the orbiting scroll can be reduced, and the compression efficiency is increased. Can do. And the temperature in a lap | wrap part can be reduced and lifetime, such as a chip seal, can be extended. Moreover, when the closest part is formed in the tooth tip part where the thermal collapse of the wrap part is noticeable, the closest part can prevent galling due to the thermal collapse.

  Furthermore, on the tooth base side of the wrap portion, the gap between the outer peripheral surface of the wrap portion and the inner peripheral surface of the counterpart lap portion can be set to be approximately the same as the interval dimension when the closest approach portion is not provided. Therefore, the contact of the lap portion at this position can be prevented, and the reliability can be improved.

  According to the invention of claim 7, each closest approach portion is formed only on the inner diameter side in the winding direction of the wrap portion, and the involute curved surface portion is provided on the outer diameter side of the wrap portion. At the closed position or the like of the compression chamber defined on the outer diameter side, the smooth peripheral surfaces of the lap portions can be brought closest to or in contact with each other. Thereby, it is possible to satisfactorily seal the outer diameter side compression chamber having a great influence on the volumetric efficiency at the time of compression, and to improve the compression performance.

  In particular, since the temperature rise due to the compression heat is small on the outer peripheral side of the lap portion, the galling phenomenon is unlikely to occur. For this reason, in the involute curved surface part provided in the outer peripheral side of the lap | wrap part, the clearance gap dimension with the other wrap part can be made small. As a result, smooth peripheral surfaces on the outer diameter side of each lap portion can be brought closest to or in contact with each other, and abnormal noise generated by the closest approach portion on the inner diameter side of the lap portion is sucked on the outer diameter side, etc. Can be prevented from leaking outside.

  Hereinafter, a scroll type air compressor will be described as an example of a scroll type fluid machine according to an embodiment of the present invention, and will be described in detail with reference to the accompanying drawings.

  Here, FIG. 1 to FIG. 6 show a first embodiment. In this embodiment, the case where the closest part is provided on the outer peripheral surface of the wrap part of the fixed scroll and the orbiting scroll will be described as an example.

  FIG. 1 is a longitudinal sectional view of a scroll type air compressor. In FIG. 1, 1 is a fixed scroll of the scroll type air compressor, and the fixed scroll 1 is a casing (not shown) formed in a cylindrical shape. At the end of the. Further, the fixed scroll 1 is formed in a substantially disc shape and is erected on the end plate 2 disposed so that the center thereof coincides with an axis O1-O1 of a drive shaft 9 which will be described later, and on the surface 2A of the end plate 2. A spiral wrap portion 3, a cylindrical portion 4 that protrudes in the axial direction so as to surround the wrap portion 3 from the outer diameter side of the end plate 2, and a flange portion 5 that expands radially outward from the cylindrical portion 4 It is roughly structured.

  2 is a cross-sectional view of the scroll type air compressor shown in FIG. 1. As shown in FIG. 2, the wrap portion 3 has an inner diameter side (inner side in the radial direction) as a winding start end and an outer diameter side. (Outside in the radial direction) is formed in a spiral shape that becomes the end of winding. Moreover, 3 A of inner peripheral surfaces of the lap | wrap part 3 are formed as a concave curved smooth surface without an unevenness | corrugation. On the other hand, the outer peripheral surface 3B of the wrap part 3 is formed in a polygonal shape by connecting a plurality of flat surfaces 8A described later. Then, as shown in FIG. 6, the lap portion 3 is cut into a spiral shape using a cutting tool such as an end mill.

  Further, as shown in FIG. 1, the fixed scroll 1 is provided with a suction port 6 that is located on the outer diameter side of the end plate 2 and sucks air into a compression chamber 15 described later. A discharge port 7 is provided for discharging the air compressed in step S2.

  8, 8,... Are a plurality of closest portions provided on the outer peripheral surface 3B side of the wrap portion 3, and each of the closest portions 8 is arranged in the winding direction of the wrap portion 3 as shown in FIGS. (Length direction) are arranged at intervals, and are formed extending in the axial direction. At this time, the angle α between the adjacent closest portions 8 is set to, for example, about 5 degrees (α = 0.087 [rad]).

  Moreover, it is set as the structure connected between the nearest approach parts 8 using the flat surface 8A. Thereby, the outer peripheral surface 3B of the lap portion 3 is formed in a polygonal cross section, and each closest approach portion 8 is disposed at the apex (bent portion) of the outer peripheral surface 3B having a polygonal shape. And the closest approach part 8 contacts or is closest to the inner peripheral surface 13A of the lap part 13 of the orbiting scroll 11 as the opponent.

  Note that the portion where the wrap portion 3 of the fixed scroll 1 and the wrap portion 13 of the orbiting scroll 11 are closest to each other changes with the orbiting motion of the orbiting scroll 11, and the end of winding (the outer diameter side) of the wrap portions 3 and 13. ) Gradually toward the winding start end (inner diameter side). For this reason, there may be a state in which the flat surface 8 </ b> A is closest to the lap portion 13 of the orbiting scroll 11 than the closest portion 8. However, the closest part 8 points out the vertex part of the outer peripheral surface 3B which makes polygonal shape. For this reason, the distance dimension in the state in which the closest part 8 and the lap part 13 are closest is smaller than the distance dimension in the state in which the flat surface 8A and the lap part 13 are closest. That is, the flat surface 8 </ b> A is separated from the inner peripheral surface 13 </ b> A of the wrap portion 13 of the orbiting scroll 11 rather than the closest portion 8.

  A drive shaft 9 is rotatably provided on the casing, and the drive shaft 9 has an axis O1-O1 serving as a rotation center. Further, the drive shaft 9 is a crankshaft 9A that is eccentrically extended at the front end side of the fixed scroll 1, and the axis O2-O2 that is the center line of the crankshaft 9A has a turning radius with respect to the axis O1-O1 of the drive shaft 9 It is eccentric by ε. A turning scroll 11 (described later) is rotatably attached to the crankshaft 9 </ b> A of the drive shaft 9 via a turning bearing 10.

  Reference numeral 11 denotes a orbiting scroll provided on the drive shaft 9 so as to face the fixed scroll 1. The orbiting scroll 11 includes an end plate 12 formed in a disc shape around an axis O 2 -O 2, and a surface of the end plate 12. It is roughly constituted by a spiral wrap portion 13 erected in the axial direction from 12A.

  The orbiting scroll 11 is arranged such that the lap portion 13 overlaps the lap portion 3 of the fixed scroll 1 with a shift of 180 degrees, for example. Thereby, a plurality of compression chambers 15 to be described later are defined between the lap portions 3 and 13 of both. When the scroll type air compressor is operated, the outer peripheral side compression chamber 15 sucks air from the suction port 6 and sequentially compresses this air while moving to the inner diameter side while the orbiting scroll 11 is revolving. Compressed air is discharged from the discharge port 7 to the outside.

  Here, the lap portion 13 constituting the orbiting scroll 11 is erected on the surface 12A of the end plate 12 in the axial direction (direction of the axis O1-O1). The wrap portion 13 is formed in a spiral shape consisting of n turns, the inner diameter side of which is the winding start end and the outer diameter side of which is the winding end end. Further, the inner peripheral surface 13A of the wrap portion 13 is formed as a concave curved smooth surface without unevenness. On the other hand, the outer peripheral surface 13B of the wrap part 13 is formed in a polygonal shape in which a plurality of flat surfaces 14A described later are connected. Then, as shown in FIG. 6, the lap portion 13 is cut into a spiral shape using a cutting tool such as an end mill, for example.

  14, 14,... Are a plurality of closest portions provided on the outer peripheral surface 13 </ b> B side of the lap portion 13, and each closest approach portion 14 is substantially the same as the closest portion 8 as shown in FIGS. 2 and 3. The wrap portion 13 is disposed with a gap in the winding direction (length direction) and extends in the axial direction. At this time, the angle α between the adjacent closest portions 14 is set to, for example, about 5 degrees (α = 0.087 [rad]).

  Moreover, it is set as the structure connected using the flat surface 14A between the adjacent closest parts 14. FIG. Thereby, the outer peripheral surface 13B of the wrap portion 13 is formed in a polygonal cross section, and each closest approach portion 14 is disposed at the apex (bent portion) of the outer peripheral surface 13B having a polygonal shape. And the closest approach part 14 contacts or approaches the inner peripheral surface 3A of the lap | wrap part 3 of the fixed scroll 1 used as the other party.

  The portion where the wrap portion 3 of the fixed scroll 1 and the lap portion 13 of the orbiting scroll 11 are closest to each other changes with the orbiting motion of the orbiting scroll 11. For this reason, there may be a state in which the flat surface 14 </ b> A is closest to the lap portion 3 of the fixed scroll 1 rather than the closest portion 14. However, the closest approach part 14 points out the vertex part of the outer peripheral surface 13B which makes polygonal shape. For this reason, the distance dimension in the state in which the closest part 14 and the lap part 3 are closest is smaller than the distance dimension in the state in which the flat surface 14A and the lap part 3 are closest. That is, the flat surface 14 </ b> A is farther from the inner peripheral surface 3 </ b> A of the wrap portion 3 of the fixed scroll 1 than the closest portion 14.

  Here, the detailed arrangement relationship of the closest part 14 provided in the outer peripheral surface 13B of the lap | wrap part 13 of the turning scroll 11 is demonstrated.

  The closest part 14 is formed such that the interval dimension P in the winding direction which is the length direction of the wrap part 13 is narrow on the inner diameter side and wider on the outer diameter side. Here, the arrangement of the closest portions 14 will be described in detail. The orbiting scroll 11 has a center point O2 (axis O2−) to draw an involute (expanded line) of the wrap portion 13 as shown in FIG. A contracted line C having a contracted line radius a centered on (the position of O2) is obtained. The contraction line radius a is a value unique to the orbiting scroll 11 determined by the orbiting radius ε and the thickness of the lap portion 13 of the orbiting scroll 11, and is a known item in the involute curve.

  Then, among the innumerable tangent lines extending in contact with the contracted line C, an arbitrary tangent line is defined as L1, and other tangent lines provided at positions shifted by an angle α from the tangent line L1 are defined as L2, L3,. The closest part 14 is disposed on each of the tangents L1, L2,.

  Here, in the present embodiment, the angle α between the tangents L1, L2,... Is set to about 5 degrees. Thereby, the space | interval dimension P of the winding direction of the adjacent closest part 14 is narrow at the 1st volume used as the internal diameter side of the lap | wrap part 13, and is wide at the nth roll used as the outer diameter side.

  In this way, by narrowing (smaller) the distance P between the adjacent closest approaching portions 14 on the inner diameter side, the closest approaching portion can be applied even to a portion where the radius of curvature of the facing wrap portion 3 is small and sharply bends. 14 can be arranged on the inner peripheral surface 3A of the lap portion 3 with a predetermined gap.

  Further, when the closest approach portion 14 approaches the inner peripheral surface 3A of the lap portion 3 on the fixed scroll 1 side facing, the clearance dimension S2 between the closest peripheral portion 14 and the inner peripheral surface 3A of the wrap portion 3 becomes the following formula 1. As shown, the clearance dimension S1 between the closest approach portion 8 and the inner peripheral surface 13A when approaching the inner peripheral surface 13A of the lap portion 13 on the side of the orbiting scroll 11 facing the closest approach portion 8 is larger. Is set.

  Thus, since the gap dimension S2 between the closest part 14 and the lap part 3 is larger than the gap dimension S1 between the closest part 8 and the lap part 13, each of the lap parts 3, 13 is used. If contact occurs, the closest portion 8 provided on the outer peripheral surface 3B of the wrap portion 3 of the fixed scroll 1 before the closest portion 14 and the outer peripheral surface 3B of the wrap portion 3 contact each other. Can be brought into contact with the outer peripheral surface 13 </ b> B of the lap portion 13 of the orbiting scroll 11.

  Then, when the closest approach portion 8 of the lap portion 3 of the fixed scroll 1 comes into contact with the lap portion 13 of the orbiting scroll 11 first, the orbiting scroll 11 is rotated in the same direction as the direction of the rotation force with the contact portion as a fulcrum. Force to act. As a result, the orbiting scroll 11 is pushed in the direction of the rotation force. For example, the rattling of a rotation prevention mechanism (not shown) provided between the orbiting scroll 11 and the casing can be eliminated. it can.

  On the other hand, each closest approach portion 8 provided on the outer peripheral surface 3B of the lap portion 3 of the fixed scroll 1 has the same conditions as the conditions relating to the arrangement relationship of the closest approach portion 14 described above, and thus the description thereof is omitted. Shall.

  In addition, although the closest approach part 8 and 14 was set as the structure provided in the full length of the winding direction of the lap | wrap parts 3 and 13, for example, among the full length of the wrapping parts 3 and 13 of the winding direction, the winding start which becomes the inner diameter side most You may form in the outer peripheral surfaces 3B and 13B except the site | part about a half turn from the end. In the outer circumferential surfaces 3B and 13B of the wrap portions 3 and 13, the portion of the winding around the half turn from the winding start end has the smallest radius of curvature and the dimensional change due to heat is small. This is because the compression chamber 15 can be sufficiently sealed, and this portion is formed as a smooth surface.

  The scroll type air compressor according to the present embodiment has the above-described configuration. Next, the operation of the scroll type air compressor will be described.

  First, when the drive shaft 9 is rotationally driven by a drive source (not shown) such as an electric motor, the orbiting scroll 11 is centered on the axis O1-O1 of the drive shaft 9 in a state where the rotation is prevented by the rotation prevention mechanism. The orbiting motion with the orbiting radius ε is performed, and the compression chamber 15 defined between the lap portion 3 of the fixed scroll 1 and the lap portion 13 of the orbiting scroll 11 is continuously reduced. As a result, the air sucked from the suction port 6 of the fixed scroll 1 can be sequentially compressed in the respective compression chambers 15 and discharged from the discharge port 7 of the fixed scroll 1 toward the external tank (not shown) as compressed air. it can.

  Further, when the orbiting scroll 11 orbits with respect to the fixed scroll 1, the closest approach parts 8 and 14 and the inner peripheral surfaces 13 </ b> A and 3 </ b> A of the lap parts 13 and 3 are closest to each other, or both are in contact with each other. These closest approaches (contacts) become the closed positions where the air is confined in the compression chambers 15. And the closest approach part 8 reduces the clearance gap between the outer peripheral surface 3B of the lap | wrap part 3, and the inner peripheral surface 13A of the lap | wrap part 13 in the closed position of each compression chamber 15. FIG. Further, the closest portion 14 reduces the gap between the outer peripheral surface 13B of the wrap portion 13 and the inner peripheral surface 3A of the wrap portion 3 at the closed position of each compression chamber 15. Thereby, the closest approach parts 8 and 14 can improve the sealing property of each compression chamber 15.

  However, in the present embodiment, the outermost surfaces 3B and 13B of the wrap portions 3 and 13 of the scrolls 1 and 11 are provided with a plurality of closest approach portions 8 and 14 at intervals in the winding direction. , 14 are connected by flat surfaces 8A, 14A so that the outer peripheral surfaces 3B, 13B are formed in a polygonal shape. At this time, since the adjacent closest portions 8 and 14 are connected to each other using the flat surfaces 8A and 14A, a concave portion that is depressed in the radial direction is formed between the adjacent protrusions as in the prior art. There is no. For this reason, the space | interval of the lap | wrap parts 3 and 13 which mutually face can be narrowed, the air stagnated between the lap | wrap parts 3 and 13 can be reduced, and compression efficiency can be improved.

  Moreover, since it was set as the structure which connects between the nearest closest parts 8 and 14 using flat surface 8A, 14A, the cross section of the outer peripheral surfaces 3B and 13B of the lap | wrap parts 3 and 13 can be formed in polygonal shape. . For this reason, the shape of the wrap parts 3 and 13 can be simplified compared with the case where protrusions are provided on the peripheral surface of the wrap part formed of a curved surface as in the prior art. As a result, even when the lap portions 3 and 13 are cut using a tool such as an end mill, the end mill does not need to be reciprocated in the radial direction along the protrusions, and the number of times of tool direction change is reduced. be able to. For this reason, a processing error of about 5 μm generally occurs in a processing machine due to backlash during reciprocating operation, but in this embodiment, it is difficult to be affected by such backlash and the processing error is reduced. It is possible to process the highly accurate lap portions 3 and 13 with little variation.

  Further, compared to the case where the protrusions are provided as in the prior art, the moving distance of the tool such as the end mill is shortened and the number of times of changing the direction of the tool can be reduced. It can be shortened and productivity can be improved. Furthermore, a machining program can be easily set up simply by giving the vertex coordinates of the polygonal shape, and the vertex coordinates can be easily changed. For example, the shape of the wrap parts 3 and 13 can be easily adapted to the specifications of the compressor. Can be changed.

  Moreover, since the closest part 8 of the lap | wrap part 3 surface-contacts with the inner peripheral surface 13A of the other party's lap | wrap part 13 in the state close | similar to a line contact, the closest part 8 is easily crushed and worn by this contact. be able to. For this reason, the closest approach part 8 of the lap | wrap part 3 can adapt to 13 A of inner peripheral surfaces of the lap | wrap part 13, without contacting many times. Similarly, the closest approach portion 14 of the wrap portion 13 can be easily adapted to the inner peripheral surface 3 </ b> A of the counterpart lap portion 3. As a result, power loss can be reduced, damage, noise, galling and the like can be prevented, and durability and reliability can be improved.

  Further, when the angle α between the adjacent closest portions 8 and 14 of the wrap portions 3 and 13 is increased, the inner angle of the closest portions 8 and 14 (the angle formed by the two adjacent flat surfaces 8A and 14A) becomes a sharper angle. As a result, galling resistance is improved, but the gap between the flat surface 8A and the outer peripheral surface 13A and the gap between the flat surface 14A and the outer peripheral surface 3A are increased, so that the compression performance is lowered. On the other hand, if the angle α between the adjacent closest approach parts 8 and 14 of the wrap parts 3 and 13 is reduced, the inner angle of the closest approach parts 8 and 14 becomes a more obtuse angle. Since the gap between the outer circumferential surface 13A and the gap between the flat surface 14A and the outer circumferential surface 3A is reduced, the compression performance is improved. For this reason, for example, by setting the angle α to about 5 degrees (α = 0.087 [rad]), such a conflicting balance can be optimized, and the anti-galling property and the compression performance can be balanced. Compressors can be manufactured.

  On the other hand, the adjacent closest portions 8 and 14 are arranged with an interval of an angle α of about 5 degrees, so that the interval dimension P in the winding direction of the wrap portions 3 and 13 is narrow on the inner diameter side and on the outer diameter side. It is formed to be wide. As a result, even when the wrap portions 3 and 13 have a small radius of curvature and a sharp bend, the closest approach portions 8 and 14 in which the spacing dimension P in the winding direction is narrowed are within the other wrap portions 13 and 3. It can arrange | position so that it may approach along the surrounding surfaces 13A and 3A, can improve the sealing performance of the compression chamber 15, and can improve compression performance.

  Furthermore, the clearance dimension S1 between the closest approach portion 8 of the wrap portion 3 of the fixed scroll 1 and the inner peripheral surface 13A of the wrap portion 13 of the orbiting scroll 11 and the closest approach portion 14 of the wrap portion 13 of the orbiting scroll 11 are fixed. The gap dimension S2 between the scroll 1 and the inner peripheral surface 3A of the lap portion 3 is set in a relationship of S1 <S2 as shown in Equation 1. Thereby, when contact arises between each lap | wrap parts 3 and 13, the innermost peripheral surface of the closest approach part 8 provided in the outer peripheral surface 3B of the lap | wrap part 3 of the fixed scroll 1, and the lap | wrap part 13 of the turning scroll 11 13A can be contacted first. For this reason, the orbiting scroll 11 can be rotated in the same direction as the direction of the rotation force with the contact part as a fulcrum, and the compression performance is improved by preventing the rotation of the rotation prevention mechanism (not shown) and the like. Can do.

  In the first embodiment, the adjacent closest portions 8 and 14 are connected using the flat surfaces 8A and 14A. However, the present invention is not limited to this. For example, as in the first modified example shown in FIG. 7, the adjacent closest approach portions 8 and 14 may be connected using convex curved surfaces 8A ′ and 14A ′. Good. In this case, the convex curved surfaces 8A ′ and 14A ′ are arranged so that the wrap portions 3 and 3A do not come into contact with the inner peripheral surfaces 13A and 3A of the counterpart wrap portions 13 and 3 before the closest portions 8 and 14. It is formed with a curvature smaller than the curvature of 13.

  In the first embodiment, the closest approach portions 8 and 14 are provided in both the wrap portion 3 of the fixed scroll 1 and the wrap portion 13 of the orbiting scroll 11. It is good also as a structure which provides a closest approach part only in any one of them.

  Further, the closest portions 8 and 14 may be configured to have, for example, a flat surface having a slight width (for example, about several μm) in the winding direction at the tip portion.

  Further, in the first embodiment, the closest approach portions 8 and 14 adjacent from the inner diameter side to the outer diameter side of the wrap portions 3 and 13 are formed with an equal angle α. However, the present invention is not limited to this, and the closest approach portions on the inner diameter side and the outer diameter side of the wrap portion may be formed at different angular intervals.

  Next, FIGS. 8 and 9 show a second embodiment according to the present invention. The feature of this embodiment is that a flat closest surface is wound on the inner peripheral surface of the wrap portion of each scroll in the winding direction. The configuration is such that a plurality are provided at intervals. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  Reference numeral 21 denotes a fixed scroll of a scroll type air compressor, and the fixed scroll 21 is constituted by an end plate 22, a lap portion 23, a cylindrical portion 24, a flange portion (not shown), etc., as in the first embodiment. Has been. The wrap portion 23 is formed in a spiral shape having an inner peripheral surface 23A and an outer peripheral surface 23B.

  25 are a plurality of closest portions provided on the outer peripheral surface 23B side of the lap portion 23, and each of the closest portions 25 is substantially the same as the closest portion 8 according to the first embodiment. The portions 23 are arranged at intervals of an angle α in the winding direction (length direction) and extend in the axial direction. Moreover, it is set as the structure connected using the flat surface 25A between the adjacent closest parts 25. FIG. Thereby, the outer peripheral surface 23B of the lap | wrap part 23 is formed in the polygonal cross section. And the closest approach part 25 contacts or is closest to the inner peripheral surface 28A of the lap part 28 of the orbiting scroll 27 as the opponent.

  26, 26,... Are a plurality of flat closest surfaces provided on the inner peripheral surface 23A side of the lap portion 23, and each of the closest surfaces 26 is, for example, the closest portion in the winding direction (length direction). 29 are arranged at the same angle α. Further, the adjacent closest approach surfaces 26 are connected using a recess 26A that is recessed in a direction away from the lap portion 28 of the orbiting scroll 27 (outside in the radial direction). Thereby, the inner peripheral surface 23A of the wrap part 23 is formed in a polygonal cross section. Further, the adjacent depressions 26 </ b> A are arranged at positions shifted by half the phase with respect to the closest approaching part 29 of the other party. As a result, the intermediate portion in the winding direction of the closest approach surface 26 is in contact with or closest to the closest approach portion 29 provided on the outer peripheral surface 28 </ b> B of the counterpart lap portion 28. The hollow portion 26A is formed in a curved surface shape having a radius similar to the radius of the tool in accordance with the cutting by an end mill or the like.

  Reference numeral 27 denotes a orbiting scroll disposed opposite to the fixed scroll 21. The orbiting scroll 27 is substantially the same as in the first embodiment, and the spiral wrap portion 28 is provided upright on an end plate (not shown). The wrap portion 28 has an inner peripheral surface 28A and an outer peripheral surface 28B.

  29, 29,... Are a plurality of closest portions provided on the outer peripheral surface 28B side of the lap portion 28, and each of the closest portions 29 is substantially the same as the closest portion 14 according to the first embodiment. The portions 28 are arranged at intervals of an angle α in the winding direction (length direction) and extend in the axial direction. Moreover, it is set as the structure connected between the nearest approach parts 29 using the flat surface 29A.

  30 are a plurality of flatest closest surfaces provided on the inner peripheral surface 28A side of the lap portion 28, and each of the closest surfaces 30 is, for example, the closest portion in the winding direction (length direction). Are arranged with the same angle α as 25. Further, the adjacent closest approach surfaces 30 are connected using a recess 30 </ b> A that is recessed in a direction away from the lap portion 23 of the fixed scroll 21. Further, the adjacent recessed portions 30 </ b> A are arranged at a position shifted by half the phase with respect to the counterpart closest approach portion 25.

  Thereby, as for the inner peripheral surface 28A and the outer peripheral surface 28B of the lap | wrap part 28, all have the cross section formed in the polygonal shape. The closest approach portion 29 is in contact with or closest to the closest approach surface 26, and the closest approach surface 30 is in contact with or closest to the closest approach portion 25.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. In particular, in the present embodiment, the inner peripheral surfaces 23A, 28A of the wrap portions 23, 28 are provided with a plurality of flat closest approach surfaces 26, 30 at intervals in the winding direction. Compared to the case where the curved surface is formed along an involute curve, the closest portions 25 and 29 and the closest surfaces 30 and 26 are in surface contact with each other in a state closer to line contact. That is, even when the angle α between the adjacent closest portions 25 and 29 is set to the same value as that in the first embodiment, the galling resistance can be further improved as compared with the first embodiment. .

  Further, since the inner peripheral surfaces 23A and 28A of the wrap portions 23 and 28 are provided with a plurality of flat closest approach surfaces 26 and 30 at intervals in the winding direction, the outer peripheral surfaces of the wrap portions 23 and 28 of the scrolls 21 and 27 are provided. In addition to 23B and 28B, the cross sections of the inner peripheral surfaces 23A and 28A can also be formed in a polygonal shape. For this reason, since the shape of the lap | wrap parts 23 and 28 can be simplified, the processing time of the lap | wrap parts 23 and 28 can further be shortened, and productivity can be improved.

In the second embodiment, the closest surfaces 26 and 30 are formed by flat surfaces. However, the present invention is not limited to this. For example, as shown by the alternate long and short dash line in FIG. 10, the closest approach surfaces 26 ′ and 30 ′ may be formed using concave curved surfaces (concave curved surfaces). In this case, the curvature of the closest approach surfaces 26 ′ and 30 ′ is the involute curve of each lap portion 23, 28 so that only the intermediate portion contacts the outer peripheral surfaces 28 B, 23 B of the other lap portion 28, 23. Set a value smaller than the curvature. Thereby, compared with the case where the closest approach surfaces 26 and 30 are formed by flat surfaces, the galling resistance is lowered, but the interval between the wrap portions 23 and 28 is narrowed, and the compression performance is improved.
On the other hand, as shown by a two-dot chain line in FIG. 10, the closest approach surfaces 26 ″ and 30 ″ may be formed using a convex curved surface (convex curved surface). In this case, the compression performance is reduced as compared with the case where the closest approach surfaces 26 and 30 are formed by flat surfaces, but the anti-galling property is improved.

  In the second embodiment, the closest approach surfaces 26 and 30 are provided on both the lap portion 3 of the fixed scroll 1 and the lap portion 13 of the orbiting scroll 11. It is good also as a structure which provides the closest approach surface only in any one of them.

  Next, FIG. 11 shows a third embodiment according to the present invention. The feature of this embodiment is that a soft film is provided on the outer peripheral surface of the wrap portion of each scroll. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  31 is a soft coating provided on the outer peripheral surface 3B of the wrap portion 3 of the fixed scroll 1, and the soft coating 31 is a resin material (for example, fluorine-based resin or the like) or a non-resin having good slidability and heat resistance. It is formed using a material (for example, graphite, molybdenum disulfide, boron nitride, etc.), and the film thickness is set to about 60 μm, for example. And the soft film 31 is apply | coated and fixed to the lap | wrap part 3 using application means, such as dipping and a spray, for example. Thereby, the soft coating 31 covers the closest portion 8 and the flat surface 8A provided on the outer peripheral surface 3B of the wrap portion 3.

  32 is a soft coating provided on the outer peripheral surface 13B of the wrap portion 13 of the orbiting scroll 11, and the soft coating 32 is made of, for example, a fluorine-based resin material or a non-resin material such as molybdenum-based material in substantially the same manner as the soft coating 31. For example, it is formed with a film thickness of about 60 μm, and is applied and fixed to the lap portion 13 using an application means such as spray. Thereby, the soft coating 32 covers the closest part 14 and the flat surface 14 </ b> A provided on the outer peripheral surface 13 </ b> B of the wrap part 13.

  The soft coatings 31 and 32 are assumed that the closest parts 8 and 14 are too close to the other lap parts 13 and 3 due to, for example, dimensional errors and assembly errors of the scrolls 1 and 11 and the closest parts 8 and 14. Moreover, it prevents that the closest approach part 8 and 14 and the other party's lap | wrap parts 13 and 3 contact directly.

  Furthermore, the film thicknesses of the soft coatings 31 and 32 are such that only the closest portions 8 and 14 arranged at the vertices of the polygon are brought into contact with each other, and the inner peripheral surfaces 13A of the closest portions 8 and 14 and the wrap portions 13 and 3 are used. , 3A, the compression efficiency can be improved by about 10% as a total adiabatic efficiency by setting the gap (gap) between 0 and minus (less than zero). As a result of the experiment, when the gap was 40 μm, the total heat insulation efficiency was 50%, whereas when the gap was 0 μm, the total heat insulation efficiency was 60%.

  Further, even when such contact occurs, the soft coatings 31 and 32 can be easily crushed or worn by contact with the other lap portions 13 and 3, and can be deformed. Can adapt to the range of movement.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. In particular, in the present embodiment, the outer peripheral surfaces 3B and 13B of the wrap portions 3 and 13 are provided with the soft coatings 31 and 32. Therefore, for example, due to a dimensional error of the machine, an assembly error, etc. When 14 approaches the other party's lap parts 13 and 3 too much, the soft members 31 and 32 contact the inner peripheral surfaces 13A and 3A of the other party's wrap parts 13 and 3. In this case, since the soft coatings 31 and 32 can be easily deformed and adapted by contact with the other lap portions 13 and 3, galling, damage, etc. occur between them, power loss, noise, etc. It is possible to prevent the increase.

  And even if the angle (alpha) between the adjacent closest parts 8 and 14 is enlarged, the largest gap between the lap | wrap parts 3 and 13 can be made small. For this reason, even when the angle α is set to, for example, about 7.5 degrees (α = 0.13 [rad]) to improve the anti-galling property, the compression performance can be kept high. As a result, both galling resistance and compression performance can be improved.

  Further, since the soft coatings 31 and 32 are deformed only at the portion sandwiched between the closest portions 8 and 14 and the wrap portion, the wrap portions 3 and 13 of the scrolls 1 and 11 at the closed position of the compression chamber 15. The size of the gap formed between them can be reduced. For this reason, the sealing property and compression efficiency of the compression chamber 15 can be improved. Further, even when the moving range of the closest approach parts 8 and 14 varies due to, for example, a dimensional error or assembly error of the machine, the soft coatings 31 and 32 can absorb the variation in the moving range of the closest approach parts 8 and 14. it can. For this reason, since processing, an assembly, etc. of the scrolls 1 and 11 can be performed with minimum precision, a compressor can be manufactured efficiently.

  In the third embodiment, the soft films 31 and 32 are provided only on the outer peripheral surfaces 3B and 13B of the wrap portions 3 and 13. However, the present invention is not limited to this. For example, the soft coating may be provided only on the inner peripheral surfaces 3A and 13A of the wrap portions 3 and 13. Moreover, the structure which provides a soft film on both surfaces of 3 A of inner peripheral surfaces and 3 A of outer peripheral surfaces of the lap | wrap part 3, and the structure which provides a soft film on both surfaces of the inner peripheral surface 13A and the outer peripheral surface 13B of a wrap part 13 may be sufficient, It is good also as a structure which provides a soft film in all the surfaces of inner peripheral surface 3A, 13A and outer peripheral surface 3B, 13B of the lap | wrap parts 3 and 13. FIG.

  Moreover, in the said 3rd Embodiment, it was set as the structure which provides the soft film 31 and 32 with respect to the lap | wrap parts 3 and 13 of the scroll 1 and 11 similar to 1st Embodiment, For example, 2nd implementation It is good also as a structure which provides a soft film with respect to the lap | wrap part of the scroll similar to this form.

  Next, FIGS. 12 to 14 show a fourth embodiment according to the present invention. The feature of this embodiment is that each closest approach portion of the lap portion is formed only in a part in the axial direction away from the end plate. It is in the configuration to do. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  Reference numeral 41 denotes a fixed scroll of a scroll type air compressor. As shown in FIG. 12, the fixed scroll 41 has a substantially disc-shaped end plate 42 and a surface of the end plate 42 as in the first embodiment. A spiral wrap portion 43 standing in the axial direction, a flange portion (not shown), and the like are included.

  Further, the inner peripheral surface 43A of the wrap portion 43 is formed as a smooth curved surface without unevenness, and the outermost surface 43B of the wrap portion 43 is provided with a closest portion 51 described later. Further, as shown in FIGS. 13 and 14, a tooth groove of the wrap portion 43 is provided with a concave groove 43 </ b> C having a U-shaped cross section, and a spiral chip seal 44 is attached to the concave groove 43 </ b> C. . The tip seal 44 is elastically slidably in contact with the surface of the end plate 48 of the orbiting scroll 47, which will be described later, to prevent leakage of compressed air.

  45 is a plurality of closest portions provided on the outer peripheral surface 43B of the wrap portion 43 of the fixed scroll 41. Each of the closest portions 45 is substantially the same as the closest portion 8 according to the first embodiment. 43 is arranged at intervals in the winding direction and extends in the axial direction. The term “extending in the axial direction” includes not only a configuration extending in parallel to the axial direction (inclination angle 0 °) but also including a configuration extending obliquely by ± 10 to 20 ° with respect to the axial direction, for example.

  Further, the closest portion 45 extends from the tooth tip of the wrap portion 43 toward the tooth base to an intermediate position in the axial direction, and is formed only on the tooth tip side in the axial direction away from the end plate 42 in the wrap portion 43. . On the other hand, between the adjacent closest portions 45 on the tooth tip side of the wrap portion 43, the flat surfaces 45A are connected. And the part (part except the closest part 45 and flat surface 45A) located in the tooth root side among the outer peripheral surfaces 43B of the lap | wrap part 43 is formed as a smooth curved surface without an unevenness | corrugation. Furthermore, the part located in the tooth root side among the outer peripheral surfaces 43B of the wrap part 43 extends continuously with the closest part 45 and forms the same surface.

  46 is a stepped portion provided on the tooth base side of the wrap portion 43 of the fixed scroll 41. The step portion 46 is formed wider than the tooth tip side of the wrap portion 43, and the inner peripheral surface 43A is the counterpart. It protrudes toward the outer peripheral surface 49B of the lap portion 49 of the orbiting scroll 47. The step portion 46 extends in the axial direction with the same length as the closest portion 51 of the lap portion 49 described later, and faces the closest portion 51.

  47 is a orbiting scroll provided to face the fixed scroll 41. As shown in FIGS. 12 and 14, the orbiting scroll 47 is substantially the same as in the first embodiment. It is generally constituted by a spiral wrap portion 49 erected in the axial direction from the surface of the end plate 48.

  Here, the inner peripheral surface 49 </ b> A of the wrap portion 49 is formed as a smooth curved surface without unevenness, and the outermost surface 49 </ b> B of the wrap portion 49 is provided with a closest portion 51 described later. Furthermore, a concave groove 49C having a U-shaped cross section is provided at the tooth tip of the wrap portion 49, and a tip seal 50 is attached to the concave groove 49C.

  Reference numeral 51 denotes a plurality of closest approach portions provided on the outer peripheral surface 49B of the lap portion 49 of the orbiting scroll 47. Each closest approach portion 51 is substantially the same as the closest approach portion 14 according to the first embodiment. 49 is arranged with a gap in the winding direction and extends in the axial direction.

  Further, the closest approach part 51 extends from the tooth tip of the wrap part 49 toward the tooth base to the midway position in the axial direction in the same manner as the closest approach part 45, and in the axial direction away from the end plate 48 of the wrap part 49. It is formed only on the tooth tip side. On the other hand, the adjacent closest portions 51 on the tooth tip side of the wrap portion 49 are connected by a flat surface 51A. And the part (part except the closest part 51 and the flat surface 51A) located in the tooth | gear base side among the outer peripheral surfaces 49B of the lap | wrap part 49 is formed as a smooth curved surface without an unevenness | corrugation. Furthermore, the part located in the tooth root side among the outer peripheral surfaces 49B of the wrap part 49 extends continuously with the closest part 51 and forms the same surface.

  52 is a step portion provided on the tooth base side of the lap portion 49 of the orbiting scroll 47, and the step portion 52 is substantially wider than the tooth tip side of the lap portion 49 in the same manner as the step portion 46 of the wrap portion 43. The inner peripheral surface 49 </ b> A is formed and protrudes toward the outer peripheral surface 43 </ b> B of the lap portion 43 of the fixed scroll 41 that is the counterpart. The step portion 52 extends in the axial direction with the same length as the closest portion 45 of the lap portion 49 and faces the closest portion 45.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. In the present embodiment, since the closest portions 45 and 51 are formed only in a part of the wrap portions 43 and 49 in the axial direction away from the end plates 42 and 48, the axial directions of the closest portions 45 and 51 are provided. The length dimension can be shortened, and the noise generated by the closest parts 45 and 51 can be reduced.

  Further, since the closest portions 45 and 51 can be made smaller with respect to the axial direction of the lap portions 43 and 49, the average radial gap between the lap portion 43 of the fixed scroll 41 and the lap portion 49 of the orbiting scroll 47 is increased. Therefore, the compression efficiency can be increased. Further, when the compression efficiency is increased, the temperature in the wrap portions 43 and 49 can be reduced, so that the lifetime of the tip seals 44 and 50 and the like can be extended.

  In particular, in the present embodiment, since the closest portions 45 and 51 are formed only at the tooth tip portions of the wrap portions 43 and 49, only the closest portion to the tooth tip portion where the thermal collapse of the wrap portions 43 and 49 occurs remarkably. 45, 51 can be arranged. As a result, it is possible to bring the closest approach portions 45 and 51 to the closest lap portions 49 and 43 while preventing galling due to thermal collapse, thereby further improving the compression efficiency.

  Further, the closest approach portions 45 and 51 are not provided on the tooth base side of the wrap portions 43 and 49, and the outer peripheral surfaces 43B and 49B of the lap portions 43 and 49 on the tooth base side are made the same curved surface as the closest approach portions 45 and 51. Since it is formed, it is possible to easily perform dimension management on the tooth base side.

  In the fourth embodiment, similarly to the first embodiment, the wraps are wrapped around the scrolls 41 and 47 provided with the closest portions 45 and 51 on the outer peripheral surfaces 43B and 49B of the wrap portions 43 and 49, respectively. The closest approach portions 45 and 51 are provided only on the tooth tip sides of the portions 43 and 49. However, the present invention is not limited to this. For example, the closest approach portion may be provided only on the tooth tip side of the wrap portion with respect to the same scroll as in the second and third embodiments.

  Next, FIG. 15 shows a fifth embodiment according to the present invention. The feature of this embodiment is that an involute curved surface portion according to an involute curve is provided on the outer diameter side of the lap portion. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  Reference numeral 61 denotes a fixed scroll of a scroll type air compressor, and the fixed scroll 61 is constituted by an end plate 62, a wrap part 63, a cylinder part 64, a flange part (not shown), etc., as in the first embodiment. Has been. The wrap portion 63 is formed in a spiral shape having an inner peripheral surface 63A and an outer peripheral surface 63B.

  However, the outer peripheral surface 63B of the wrap portion 63 is provided with a plurality of closest portions 65 and a flat surface 65A extending over the entire length in the axial direction, and on the outer diameter side (winding end side) of the wrap portion 63. An involute curved surface portion 63C according to the involute curve is provided without forming the closest portion 65. The involute curved surface portion 63C extends, for example, from the outer diameter side end portion of the wrap portion 63 toward the inner diameter side with a length of approximately one turn, and the outer diameter side compression chambers 15 ′ and 15 of the wrap portion 63. It is arrange | positioned in the site | part used as a surrounding wall of ″.

  66 is a orbiting scroll disposed opposite to the fixed scroll 61, and the orbiting scroll 66 is substantially the same as in the first embodiment, and is a spiral wrap portion 67 standing on an end plate (not shown). The wrap portion 67 has an inner peripheral surface 67A and an outer peripheral surface 67B.

  The outer peripheral surface 67B of the wrap portion 67 is provided with a closest approach portion 68 and a flat surface 68A extending over the entire length in the axial direction, and fixed to the outer diameter side (winding end side) of the wrap portion 67. Almost the same as the lap part 63 of the scroll 61, the closest part 68 is not formed on the outer diameter side, and an involute curved surface part 67C according to the involute curve is provided. The involute curved surface portion 67C extends, for example, from the outer diameter side end portion of the wrap portion 67 toward the inner diameter side with a length of approximately one and a half turns, and the compression chambers 15 'and 15 on the outer diameter side of the wrap portion 67. It is arrange | positioned in the site | part used as a surrounding wall of ″.

  As described above, in the present embodiment, the involute curved surface portions 63C and 67C are disposed in the portions of the wrap portions 63 and 67 facing the compression chambers 15 ′ and 15 ″ on the outer diameter side. During operation of the compressor, the wrap portion 63 of the fixed scroll 61 and the wrap portion 67 of the orbiting scroll 66 can be smoothly and continuously brought into sliding contact at the positions of the compression chambers 15 ′ and 15 ″ on the outer diameter side.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. In particular, in the present embodiment, an involute curved surface portion 63C is provided at a portion of approximately one turn located on the outer diameter side of the wrap portion 63 of the fixed scroll 61, and the wrap portion 67 of the orbiting scroll 66 has an outer Since the involute curved surface portion 67C is provided in the approximately one and a half turns on the radial side, the sealing performance of the compression chamber 15 'at the compression start position S and the sealing performance of the compression chamber 15 "adjacent thereto are good. Can be held in.

  Accordingly, air can be stably compressed in the outer diameter side compression chambers 15 ', 15 "having a great influence on the volumetric efficiency at the time of compression, the compression performance can be improved, and the innermost side closest portion 65, It is possible to prevent abnormal noise generated by 68 etc. from leaking to the outside through the suction port 6, and noise can be reduced.

  In the fifth embodiment, as in the first embodiment, the involute is in contrast to the scrolls 61 and 66 provided with the closest portions 65 and 68 on the outer peripheral surfaces 63B and 67B of the lap portions 63 and 67, respectively. The curved surface portions 63C and 67C are provided. However, the present invention is not limited to this, and for example, an involute curved surface portion may be provided for the scroll wrap portion similar to the second to fourth embodiments.

  Further, in each of the above-described embodiments, a scroll type air compressor that turns the orbiting scrolls 11, 27, 47, 66 with respect to the fixed scrolls 1, 21, 41, 61 fixed to the casing will be described as an example. However, the present invention is not limited to this. For example, as shown in Japanese Patent Laid-Open No. 9-133307, the present invention is applied to a full-scale rotary scroll fluid machine or the like that rotationally drives two scrolls arranged opposite to each other. You may apply.

  Further, in each of the above-described embodiments, the case where the present invention is applied to a scroll type air compressor as a scroll type fluid machine has been described as an example. However, the present invention is not limited thereto, and the invention is not limited to this. It may be applied to the scroll type fluid machine.

It is a longitudinal cross-sectional view which shows the scroll type air compressor applied to the 1st Embodiment of this invention. It is the cross-sectional view which looked at the scroll type air compressor from the arrow II-II direction in FIG. FIG. 3 is an enlarged cross-sectional view of a main part showing an enlarged view of a wrap portion of a fixed scroll and a wrap portion of a turning scroll in FIG. 2. It is an external appearance perspective view of a partial fracture which expands and shows a part of end plate of a fixed scroll, a lap part, and the closest approach part. It is a cross-sectional view of the principal part expansion which expands and shows the closest approach part of the lap | wrap part of a turning scroll. It is a cross-sectional view which shows the state which processes a lap | wrap part using an end mill. It is a cross-sectional view which shows the lap | wrap part by a 1st modification. It is a cross-sectional view which shows the scroll type air compressor applied to 2nd Embodiment. FIG. 4 is an enlarged cross-sectional view of a main part when a lap portion of a fixed scroll and a turning scroll is viewed from the same position as in FIG. 3. It is a cross-sectional view which shows the lap | wrap part by a 2nd modification. It is the cross-sectional view of the principal part expansion which looked at the lap | wrap part of the fixed scroll and turning scroll by 3rd Embodiment from the same position as FIG. It is the cross-sectional view of the principal part expansion which looked at the lap | wrap part of the fixed scroll and turning scroll by 4th Embodiment from the same position as FIG. It is an external appearance perspective view of a partial fracture which expands and shows a part of end plate of a fixed scroll, a lap part, and the closest approach part. It is the longitudinal cross-sectional view of the principal part expansion which expanded the lap | wrap part of the fixed scroll and the turning scroll from the arrow XIV-XIV direction in FIG. It is a cross-sectional view which shows the scroll type air compressor applied to 5th Embodiment.

Explanation of symbols

1, 21, 41, 61 Fixed scroll 2, 12, 22, 42, 48, 62 End plate 3, 13, 23, 28, 43, 49, 63, 67 Lapping part 3A, 13A, 23A, 28A, 43A, 49A, 63A, 67A Inner peripheral surface 3B, 13B, 23B, 28B, 43B, 49B, 63B, 67B Outer peripheral surface 8, 14, 25, 29, 45, 51, 65, 68 Nearest part 8A, 14A, 25A, 29A, 45A , 51A, 65A, 68A Flat surface 8A ', 14A' Convex curved surface 9 Drive shaft 11, 27, 47, 66 Orbiting scroll 26, 30, 26 ', 30', 26 ", 30" Closest surface 31, 32 Soft Coating

Claims (7)

One scroll having a wrap portion wound in a spiral shape from the inner diameter side to the outer diameter side on the end plate is provided in the axial direction, and a wrap of the one scroll is provided on the end plate so as to face the one scroll. Scroll fluid comprising: a wrap portion wound in a spiral shape from the inner diameter side to the outer diameter side so as to overlap with the portion and defining a plurality of compression chambers, and the other scroll in the axial direction. In the machine
On the outer peripheral surface of at least one of the scroll wrap portions, a plurality of closest approach portions that are in contact with or closest to the inner peripheral surface of the other scroll wrap portion are provided at intervals in the winding direction.
Between the adjacent closest parts, it is configured to connect using a flat surface or a convex curved surface,
The scroll fluid machine according to claim 1, wherein the flat surface or the convex curved surface is separated from the other scroll than the closest portion.   The inner surface of the wrap portion of the other scroll is closest to the closest portion provided on the outer peripheral surface of the wrap portion of the one scroll, and is closest to the flat shape, concave curve shape or convex curve shape. The scroll fluid machine according to claim 1, wherein a plurality of surfaces are provided at intervals in the winding direction.   At least one of the outer peripheral surface of the wrap portion of the one scroll and the inner peripheral surface of the wrap portion of the other scroll is formed in a film shape using a softer material than the closest portion. The scroll fluid machine according to claim 1 or 2, wherein a soft coating is provided.   4. The scroll fluid machine according to claim 1, wherein each closest approach portion is configured so that a spacing dimension in a winding direction is narrow on the inner diameter side and wider on the outer diameter side.   5. The scroll fluid machine according to claim 1, 2, 3, or 4, wherein each closest approach portion is formed with an equal angular interval from an inner diameter side to an outer diameter side of the lap portion.   The scroll type according to claim 1, 2, 3, 4, or 5, wherein each closest approach portion is formed only in a part of an axial direction away from the end plate among the lap portions provided upright on the end plate. Fluid machinery.   Each of the closest portions is formed only on the inner diameter side in the winding direction of the wrap portion, and an involute curved surface portion according to an involute curve is provided on the outer diameter side of the wrap portion. , 4, 5 or 6.

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